Type-B Energetic Processes: Their Identification and Implications

Abstract

We have now identified two thermodynamically distinct types (A and B) of energetic processes naturally occurring on Earth. Type-A energy processes, such as classical heat engines, apparently well follow the second law of thermodynamics; Type-B energy processes, such as the newly discovered thermotrophic function that isothermally utilizes environmental heat energy to perform useful work in driving ATP synthesis, follow the first law of thermodynamics (conservation of mass and energy) but do not have to be constrained by the second law, owing to their special asymmetric functions. Several Type-B energy processes such as asymmetric function-gated isothermal electricity production and epicatalysis have been created through human efforts. The innovative efforts in Type-B processes to enable isothermally utilizing endless environmental heat energy could help to liberate all peoples from their dependence on fossil fuel energy, thus helping to reduce greenhouse gas CO₂ emissions and control climate change towards a sustainable future for humanity on Earth. In addition to the needed support for further research, development, and commercialization efforts, currently, better messaging and education on Type-B energetic processes are also highly needed to achieve the mission.

1. The Discovery of Type-B Energetic Processes in Biological Systems

Recently, through bioenergetics studies with the transmembrane electrostatically localized protons (TELPs) theory, it was surprisingly discovered that “environmental heat energy can be isothermally utilized through TELPs” to help drive ATP synthesis in many biological systems including alkaliphilic bacteria [1], mitochondria [2], and anaerobic acetate-utilizing methanogenic archaea Methanosarcina [3]. That is, “the protonic bioenergetic systems have a thermotrophic feature that can isothermally utilize environmental heat (dissipated-heat energy) through TELPs with asymmetric membrane structures to generate significant amounts of Gibbs free energy to drive ATP synthesis” [4,5].

This discovery has now led to a fundamentally new major understanding that “there are two thermodynamically distinct types (A and B) of energetic processes naturally occurring on Earth” [4]. Type-A energy processes such as classical heat engines, and many of the known chemical, electrical, and mechanical processes, apparently well follow the second law; Type-B energy processes as exemplified by the thermotrophic function that “isothermally utilizes environmental heat energy associated with TELPs” does not necessarily have to be constrained by the second law, “owing to its special asymmetric function” [1,2,4]. The scientific evidence that supports this discovery is reviewed and presented as follows.

2. The Evidence in Alkaliphilic Bacteria for a Protonic Thermotrophic Function: Type-B Energetic Process

The evidence [1] for the protonic thermotrophic function in alkaliphilic bacteria has been shown with the Gibbs free energy (Figure 1) as calculated from the experimental data of the alkalophilic bacterium Bacillus pseudofirmus employing the experimentally measured cation–proton exchange equilibrium constants [6] for sodium, potassium, and magnesium through the following protonic motive force (pmf) Gibbs free energy (${∆\mathrm{G}}_T$) equation updated from the newly developed TELP theory [1,4,5].

$$∆{\mathrm{G}}_T=-F∆\psi -2.3RT {\log }_{10}\left(\frac{\left[H_{pB}^{+}\right]}{\left[H_{nB}^{+}\right]}\right)-2.3RT {\log }_{10}\left(1+\left[H_L^{+}\right]/\left[H_{pB}^{+}\right]\right)$$

(1)

Here, $∆\psi$ is the transmembrane potential from the positive (p)-side to the negative (n)-side as defined by Mitchell [7,8] and Nicholls and Ferguson [9]; $R$ is the gas constant; $T$ is the environmental temperature in Kelvins; $F$ is the Faraday constant; $\left[H_L^{+}\right]$ is the TELP concentration at the liquid–membrane interface on the p-side of the membrane; $\left[H_{pB}^{+}\right]$ is the “proton concentration in the bulk aqueous p-phase”; and $\left[H_{nB}^{+}\right]$ is the “proton concentration in the bulk liquid n-phase” [10].

As reported previously [2], the first two terms of Equation (1) comprise “the Mitchellian bulk phase-to-bulk phase proton electrochemical potential gradients” that we now call the “classic pmf” Gibbs free energy (${∆\mathrm{G}}_C$), whereas the last term accounts for the “local pmf” Gibbs free energy ($∆{\mathrm{G}}_L$) from TELPs, as shown more clearly in the following equation:

$$∆{\mathrm{G}}_L=-2.3RT {\log }_{10}\left(1+\left[H_L^{+}\right]/\left[H_{pB}^{+}\right]\right)$$

(2)

According to Equation (2), the local pmf Gibbs free energy ($∆{\mathrm{G}}_L$) is mathematically related to “the ratio ($\left[H_L^{+}\right]/\left[H_{pB}^{+}\right]$) of TELP concentration $\left[H_L^{+}\right]$ at the liquid-membrane interface to the bulk-phase proton concentration $\left[H_{pB}^{+}\right]$ at the same p-side of the membrane” [4].

Based on the TELP capacitor concept [11], the ideal TELP concentration ${\left[H_L^{+}\right]}^0$ on the p-side of the membrane is a function of the transmembrane potential $∆\psi$ as expressed in the following equation:

$${\left[H_L^{+}\right]}^0=\frac{C}{S}·\frac{∆\psi }{l·F}$$

(3)

where $C/S$ is “the specific membrane capacitance per unit surface area”, $l$ is “the thickness of the localized proton layer” [12], and $F$ is the Faraday constant.

The steady-state TELP concentration $\left[H_L^{+}\right]$ after cation–proton exchange with each of the cation species $M_{pB}^{i+}$ of the bulk liquid p-phase at the equilibrium state is as follows:

$$\left[H_L^{+}\right]=\frac{{\left[H_L^{+}\right]}^0}{\prod _{i=1}^n{ \{K}_{Pi}\left(\frac{\left[M_{pB}^{i+}\right]}{\left[H_{pB}^{+}\right]}\right)+1}$$

(4)

Here, $K_{Pi}$ is “the equilibrium constant for the cation exchange with TELP” [10]. $\left[M_{pB}^{i+}\right]$ and $\left[H_{pB}^{+}\right]$ are, respectively, the non-proton cation concentration and the delocalized proton concentration in the bulk liquid p-phase.

Surprisingly, as shown in Figure 1, very large pmf Gibbs free energy values were found, which not only can well explain how the organisms are able to synthesize ATP [13,14,15] but also significantly exceed the maximum chemical energy (NADH-to-O₂ redox potential energy limit: 22 kJ/mol) that could be supported thermodynamically by the Type-A energetic process through the respiratory redox-driven proton pump system. This finding subsequently led to the discovery that “the alkalophilic bacteria are not only chemotrophs, but also have a thermotrophic feature that can create significant amounts of Gibbs free energy through isothermal utilization of environmental heat energy with TELPs to do useful work in driving ATP synthesis” [1].

Figure 1. A Gibbs free energy graph revealing a Type-B energetic process: thermotrophic feature. The calculated total pmf energy ($∆{\mathrm{G}}_T$), local pmf energy ($∆{\mathrm{G}}_L$), and classic pmf energy ($∆{\mathrm{G}}_C$) of Bacillus pseudofirmus OF4 as a function of external pH compared to the minimally required Gibbs free energy (−11 kJ/mol) required to synthesize ATP and to the maximum chemical energy (redox potential energy limit: −22 kJ/mol) that could be supported thermodynamically by the Type-A energetic process through the respiratory redox-driven proton pump system. The measured cell population growth doubling times, reproduced from Figure 1c of Ref. [16], are also superimposed. Adapted from Ref. [1].

Figure 1. A Gibbs free energy graph revealing a Type-B energetic process: thermotrophic feature. The calculated total pmf energy ($∆{\mathrm{G}}_T$), local pmf energy ($∆{\mathrm{G}}_L$), and classic pmf energy ($∆{\mathrm{G}}_C$) of Bacillus pseudofirmus OF4 as a function of external pH compared to the minimally required Gibbs free energy (−11 kJ/mol) required to synthesize ATP and to the maximum chemical energy (redox potential energy limit: −22 kJ/mol) that could be supported thermodynamically by the Type-A energetic process through the respiratory redox-driven proton pump system. The measured cell population growth doubling times, reproduced from Figure 1c of Ref. [16], are also superimposed. Adapted from Ref. [1].

The total pmf energy, which is the sum of the local pmf energy and the classic pmf energy, is presented in Figure 1. The overall pattern of the total pmf energy amazingly matched the Bacillus pseudofirmus OF4 cell population growth observed experimentally as the cell population growth doubling times. That is, “the pattern of the total pmf energy calculated through the newly formulated pmf equations (Equations (1)–(4)) from the ground up using experimental data including the liquid culture medium pH (${pH}_{pB}$) and cation concentrations, the measured membrane potential ($∆\psi$), and cytoplasmic pH (${pH}_{nB}$) excellently matched the pattern of the observed cell population growth doubling times” [1].

As shown in Figure 1, a large part of the total pmf Gibbs free energy curve is well above the redox (chemical) potential energy limit of −22.0 kJ/mol. For example, several of the total pmf Gibbs free energies (such as −45.5, −45.2, −38.9, and −28.5 kJ/mol) are significantly larger than the chemical energy input limit of −22.0 kJ/mol through “the respiratory redox-driven proton pump system”. How could the total pmf Gibbs free energy “exceed the chemical energy limit imposed by the respiratory redox-driven proton pump system”? We now know the answer: the local pmf Gibbs free energy is from a TELP-associated thermotrophic function (a Type-B energetic process) that isothermally utilizes environmental heat (protonic thermal kinetic energy kT, which is the product of the Boltzmann constant k and temperature T contained within the $RT$ of Equation (2)) to help drive the synthesis of ATP from ADP and Pi (inorganic phosphate) through F_oF₁-ATP synthase [1].

According to Equation (2), as long as the TELP concentration $\left[H_L^{+}\right]$ is above zero, the Gibbs free energy ($∆{\mathrm{G}}_L$) change is “indeed a negative number”. That is, “the Gibbs free energy ($∆{\mathrm{G}}_L$) change for the isothermal environmental heat utilization process is indeed negative if there is a TELP concentration $\left[H_L^{+}\right]$ (above zero)” [4]. The amount of local pmf Gibbs free energy $∆{\mathrm{G}}_L$ is a function of TELP concentration $\left[H_L^{+}\right]$, as shown in Equation (2).

As shown in Figure 1, the amount of local pmf energy as calculated according to Equation (2) quantitatively represents the activity of this isothermal environmental heat (protonic thermal kinetic energy kT) utilization function with TELPs. Accordingly, it is the ratio ($\left[H_L^{+}\right]/\left[H_{pB}^{+}\right]$) of the TELP concentration $\left[H_L^{+}\right]$ at the membrane–liquid interface to the bulk-phase proton concentration $\left[H_{pB}^{+}\right]$ at the same p-side of the membrane that mathematically relates to this special isothermal environmental heat utilization function.

The local pmf energy represents a substantial portion of the total pmf energy. For example, “when the liquid culture medium pH was 7.5, the local pmf Gibbs free energy of −32.0 kJ/mol represents about 70% of the total pmf Gibbs free energy of −45.5 kJ/mol; When the liquid culture medium pH was raised to 10.5, the local pmf Gibbs free energy of −24.2 kJ/mol represents 85% of the total pmf Gibbs free energy of −28.5 kJ/mol”. Consequently, “the bacteria obtain as much as 70–85% of the total pmf Gibbs free energy from the isothermal utilization of environmental heat energy associated with TELPs”. Therefore, it is now quite clear that the bacteria have a substantial thermotrophic function (Type-B energetic process) [1,4,17] in addition to being chemotrophs (Type-A energetic process). That is, the bacteria represent a mixed chemo-thermotroph [3].

3. The Evidence for a TELP Thermotrophic Function as a Type-B Energetic Process in Mitochondria

The evidence for a Type-B energetic process (protonic thermotrophic function) in mitochondria was from the data (

Table 1. The calculated data of mitochondrial protonic thermotrophy including the transmembrane electrostatically localized proton (TELP) density per membrane surface area ($TELPs$ per µm²), TELP concentration (${[H}_L^{+}]$) at the liquid–membrane interface, TELP formation entropy change ($∆S_{LF}$), the classic protonic Gibbs free energy ($∆G_C$), the local protonic (TELP) Gibbs free energy ($∆G_L$), and the total protonic Gibbs free energy ($∆G_T$) calculated as a function of transmembrane potential $∆\psi$ using Equations (1)–(5) based on the measured properties (${pH}_{pB}$, ${pH}_{nB},$ $∆\psi )$ with the given reaction medium compositions of ref. [19] and the experimental measurements of pH across the membrane-embedded F_oF₁-ATP synthase [20]. The “cation concentrations, proton-cation exchange equilibrium constants and cation exchange reduction factor (1.29)” were from Refs. [10,11], and the temperature T = 310 K. Adapted and updated from Refs. [4,5,10], through the latest calculation using the mitochondrial inner membrane capacitance of 0.55 µf/cm² independently determined experimentally [18] and the F_oF₁-ATP synthase physiological phosphorylation potential of +55.3 kJ mol⁻¹ calculated from the measurements in the mitochondrial matrix [21].

$∆\mathit{\psi }$ mV	${\mathit{p}\mathit{H}}_{\mathit{p}\mathit{B}}$	${\mathit{p}\mathit{H}}_{\mathit{n}\mathit{B}}$	$\mathit{T}\mathit{E}\mathit{L}\mathit{P}\mathit{s}$ per µm2	${[\mathit{H}}_{\mathit{L}}^{+}]$ mM	$∆{\mathit{S}}_{\mathit{L}\mathit{F}}$ J/K·mol	$∆{\mathit{G}}_{\mathit{C}}$ kJ/mol	$∆{\mathit{G}}_{\mathit{L}}$ kJ/mol	$∆{\mathit{G}}_{\mathit{T}}$ kJ/mol	$∆{\mathit{G}}_{\mathit{S}\mathit{y}\mathit{n}}$ kJ/mol	$∆{\mathit{G}}_{\mathit{C}\mathit{h}\mathit{e}\mathit{m}}$ kJ/mol
50	7.3	7.4	1330	2.21	−88.8	−5.42	−27.5	−32.9	−20.7	−22.0
55	7.3	7.4	1460	2.43	−89.6	−5.90	−27.8	−33.7	−20.7	−22.0
60	7.3	7.4	1600	2.65	−90.3	−6.38	−28.0	−34.4	−20.7	−22.0
65	7.3	7.4	1730	2.87	−91.0	−6.86	−28.2	−35.1	−20.7	−22.0
70	7.3	7.4	1860	3.09	−91.6	−7.35	−28.4	−35.7	−20.7	−22.0
75	7.3	7.4	2000	3.31	−92.2	−7.83	−28.6	−36.4	−20.7	−22.0
80	7.3	7.4	2130	3.54	−92.7	−8.31	−28.7	−37.1	−20.7	−22.0
90	7.3	7.4	2400	3.98	−93.7	−9.28	−29.0	−38.3	−20.7	−22.0
100	7.3	7.4	2660	4.42	−94.6	−10.2	−29.3	−39.6	−20.7	−22.0
110	7.3	7.4	2930	4.86	−95.4	−11.2	−29.6	−40.8	−20.7	−22.0
120	7.3	7.4	3190	5.30	−96.1	−12.2	−29.8	−42.0	−20.7	−22.0
130	7.3	7.4	3460	5.74	−96.7	−13.1	−30.0	−43.1	−20.7	−22.0
140	7.3	7.4	3730	6.19	−97.4	−14.1	−30.2	−44.3	−20.7	−22.0
150	7.3	7.4	3990	6.63	−97.9	−15.1	−30.4	−45.4	−20.7	−22.0
160	7.3	7.4	4260	7.07	−98.5	−16.0	−30.5	−46.6	−20.7	−22.0
170	7.3	7.4	4520	7.51	−99.0	−17.0	−30.7	−47.7	−20.7	−22.0
180	7.3	7.4	4790	7.95	−99.5	−18.0	−30.8	−48.8	−20.7	−22.0
190	7.3	7.4	5060	8.40	−99.9	−18.9	−31.0	−49.9	−20.7	−22.0
200	7.3	7.4	5320	8.84	−100	−19.9	−31.1	−51.0	−20.7	−22.0

) of TELP density at the liquid–membrane interface, the TELP formation entropy change ($∆S_{LF}$), the classic protonic Gibbs free energy ($∆G_C$), the TELP Gibbs free energy ($∆G_L$), and the total protonic Gibbs free energy ($∆G_T$) calculated as a function of transmembrane potential $∆\psi$ at the physiological temperature T = 310 K through Equations (1)–(5) using the following: the mitochondrial inner membrane capacitance of 0.55 µf/cm² independently determined experimentally [18], the measured properties (${pH}_{pB}$, ${pH}_{nB},$ $∆\psi )$ with the given reaction medium compositions of Ref. [19], and the experimental measurements of pH across the membrane-embedded F_oF₁-ATP synthase [20]. The “cation concentrations, proton-cation exchange equilibrium constants and cation exchange reduction factor (1.29)” employed in the calculation were from Refs. [10,11].

Based on the F_oF₁-ATP synthase physiological phosphorylation potential of +55.3 kJ mol⁻¹ calculated from the measurements in the mitochondrial matrix [21], the physiologically required protonic Gibbs free energy ($∆G_{Syn}$) for ATP synthesis with a proton-to-ATP ratio of 8/3 in mitochondria should be −20.7 kJ mol⁻¹ (−55.3 kJ mol⁻¹/2.67). From here, we can immediately understand that even a 100% full use of “the classic Mitchellian bulk phase-to-bulk phase protonic electrochemical potential gradients” [22,23,24] is still below the physiologically required $∆G_{Syn}$ of −20.7 kJ mol⁻¹ for ATP synthesis in mitochondria. Therefore, the known NADH-to-O₂ redox chemical energy and the associated classic protonic Gibbs free energy ($∆G_C$) of the mitochondrial respiration process (Type-A energetic process) alone are not adequate to explain the ATP synthesis in mitochondria. This implicates that “there must be another fundamentally disparate biophysical energetics mechanism in mitochondria”. We have now identified it as the thermotrophic function [2,3,25], which is now known as a Type-B energetic process that can isothermally utilize environmental heat energy associated with TELPs in driving the synthesis of ATP molecules.

The calculated local protonic Gibbs free energy ($∆G_L$) is in a range from −27.5 to −31.1 kJ mol⁻¹, whereas the classic protonic Gibbs free energy ($∆G_C$) is in a range from −5.42 to −19.9 kJ mol⁻¹ for a range of transmembrane potential ($∆\psi$) from 50 to 200 mV, as shown in Table 1. “The total protonic Gibbs free energy ($∆G_T$) that is the sum of the classic protonic Gibbs free energy ($∆G_C$) and the local protonic Gibbs free energy ($∆G_L$)” was calculated to be in a range from −32.9 to −51.0 kJ mol⁻¹. Notably, “all of these $∆G_L$ and $∆G_T$ values (Table 1) are substantially above the physiologically required $∆G_{Syn}$ of −20.7 kJ mol⁻¹ for ATP synthesis at any of the transmembrane potential ($∆\psi$) values in a range from 50 to 200 mV. Therefore, the application of the newly formulated protonic Gibbs free energy equations (Equations (1)–(5)) has now consistently yielded an excellent elucidation for the energetics in mitochondria” [5].

Fundamentally, we now understand that the formation of TELPs under the transmembrane electrostatic field effect of excess protons at the p-side and excess hydroxides at the n-side represents a special “negative entropy event”. The ratio ($\left[H_L^{+}\right]/\left[H_{pB}^{+}\right]$) of the TELP concentration $\left[H_L^{+}\right]$ formed at the membrane–liquid interface to the bulk liquid-phase proton concentration $\left[H_{pB}^{+}\right]$ at the same p-side in the mitochondria intermembrane space and cristae space is related to the “negative entropy change” $∆S_{LF}$ of TELP formation, as shown in the following quantitative expression:

$$∆S_{LF}=-2.3 R {\log }_{10}\left(1+\left[H_L^{+}\right]/\left[H_{pB}^{+}\right]\right)$$

(5)

This equation was derived from Equation (2) by multiplying its two sides with (1/$T$). As shown in Equation (5), as long as the TELP concentration $\left[H_L^{+}\right]$ is above zero, the TELP formation entropy change ($∆S_{LF}$) will be a negative number. For example, the formation of TELPs that gives rise to a transmembrane potential of 100 mV will have a negative entropy change of −94.6 J/K·mol, which can be subsequently utilized to deliver a local pmf free energy ($∆G_L$) of −29.3 kJ/mol. That is, the TELP formation entropy change $∆S_{LF}$ that enables “the isothermal environmental heat utilization function as a Type-B energy process” is indeed negative as long as the TELP concentration $\left[H_L^{+}\right]$ is above zero in mitochondria.

Conversely, the local protonic Gibbs free energy ($∆G_L$) as expressed in Equation (2) for driving ATP synthesis is from the utilization of the negative entropy event-created TELP concentration $\left[H_L^{+}\right]$, thus giving rise to a positive change in TELP utilization entropy ($∆S_{LU}$) which has the same absolute of $∆S_{LF}$ but with an opposite sign. For example, the utilization of TELP concentration $\left[H_L^{+}\right]$ at a transmembrane potential of 100 mV will have a positive entropy change of +94.6 J/K·mol, delivering a local pmf energy ($∆G_L$) of −29.3 kJ/mol.

4. Mechanism of TELP Thermotrophic Function as Type-B Energetic Process

We now understand that the TELP thermotrophic function as a Type-B energy process is enabled through two key factors: (I) TELP formation and utilization (Equations (1)–(5), Table 1) and (II) the asymmetric structures of the biological membrane (Figure 2 and Figure 3) [4].

The transmembrane electrostatic proton localization is “a protonic capacitor behavior that stems from the property of liquid water as a protonic conductor and the mitochondrial inner membrane as an insulator” (Figure 2 and Figure 3) [2]. Consequently, “creating an excess number of protons on one side of the mitochondrial inner membrane accompanied by a corresponding number of hydroxide anions on the other side, for instance, through the redox-driven electron-transport-coupled proton pumps across the membrane, will result in the formation of a protonic capacitor across the biomembrane” as shown in Figure 2 and Figure 3. Accordingly, “the excess positively charged protons in cristal aqueous medium will electrostatically become localized as TELPs at the liquid-membrane interface, attracting an equal number of excess negatively charged hydroxides to the other side (matrix) of the mitochondrial inner membrane” to form a “protons-membrane-anions capacitor structure” [11]. TELP activity is now known to contribute to the amount of local protonic Gibbs free energy ($∆{\mathrm{G}}_L$) according to Equation (2).

The transmembrane asymmetric structure (Figure 2), such as that the protonic outlets of proton-pumping protein complexes I, III, and IV protrudes away from the membrane surface by at least about 1–3 nm into the bulk liquid p-phase (cristae and intermembrane space, IMS) and that the protonic inlet of the ATP synthase (complex V) is flush with membrane surface and located precisely within the TELP layer along the membrane surface, “enables effective utilization of TELP with their thermal motion kinetic energy (kT) to do useful work in driving the rotatory molecular turbine of FoF1-ATP synthase for ATP synthesis”. Consequently, “mitochondria can isothermally utilize the low-grade environmental heat energy associated with the 37 °C human body temperature to perform useful work driving the synthesis of ATP with TELPs”. Fundamentally, “it is the combination of protonic capacitor and asymmetric membrane structure that makes this amazing thermotrophic (Type-B energy process) feature possible” [4].

Furthermore, “there is a lateral asymmetric feature from the geometric effect of mitochondrial cristae (a crista typically with an ellipsoidal shape is a fold in the inner membrane of a mitochondrion) that enhances the density of TELP at the cristae tips [11], where the F₀F₁-ATP synthase enzymes are located (Figure 3) in support of the thermotrophic function” [4]. As recently reported [11], “the ratio of the TELP concentration at the crista tip (${{\left[H_L^{+}\right]}^0}_{tip}$) to that at the crista flat membrane region (${{\left[H_L^{+}\right]}^0}_{flat}$) equals the axial ratio ($a/b$) of an ellipsoidal mitochondrial crista. Consequently, for an ellipsoidal crista with a length of 200 nm and width of 20 nm, the TELP concentration at the crista tip (${{\left[H_L^{+}\right]}^0}_{tip}$) can be as high as 10 times that at the flat region (${{\left[H_L^{+}\right]}^0}_{flat}$)”. This lateral asymmetric effect “translates to a TELP associated liquid-membrane interface pH difference of about one pH unit between the crista tip (ridge) and the flat region within the same crista”. It is now known that the proton-pumping “respiratory supercomplexes” (complexes I, III, and IV) “are situated at the relatively flat membrane regions where the TELP concentration (${{\left[H_L^{+}\right]}^0}_{flat}$) is relatively lower whereas the ATP synthase dimer rows are located at the cristae ridges (tips) where the TELP concentration (${{\left[H_L^{+}\right]}^0}_{tip}$) is significantly higher”, as shown in Figure 3 [11,27,28,29,30,31,32]. Consequently, “even if the protonic outlets of the complexes I, III and IV are somehow in contact with the TELP layer at the crista flat membrane region so that their activities would be equilibrated with the redox potential chemical energy limit $∆G_{Chem}$ (−22.0 kJ mol⁻¹), the total protonic Gibbs free energy ($∆G_T$) at the crista tip can still be as high as −27.9 kJ mol⁻¹ since the TELP density at the crista tip can be as high as 10 times that of the crista flat region, equivalent to an additional effective protonic Gibbs free energy of −5.89 kJ mol⁻¹ owning to the crista geometric effect on TELPs at the liquid-membrane interface” [11].

Note, “when the axial ratio ($a/b$) equals unity (one) for a round sphere (symmetric), the density of TELP would be the same at any spot along the liquid-membrane interface for the entire spherical membrane system. Therefore, we now further understand: the ellipsoidal (asymmetric) vs the spherical (symmetric) shape change represents another revenue of spatial asymmetry that enables a lateral asymmetric TELP distribution along the crista liquid-membrane interface to increase TELP density at the crista tip (relative to the crista flat region) to enhance the TELP-associated thermotrophic function” [1,2,4,11].

5. Thermodynamic Indication of Isothermal Heat Utilization in Methanogens and Anaerobic H₂-Producing and Acetic Acid-Producing Bacteria

5.1. Isothermal Heat Utilization in Methanogens

Methanogenic bacteria [33], such as Methanosarcina sp., “can grow in an anaerobic minimal culturing medium that contains acetic acid (CH₃COOH) as the sole organic carbon source for their growth and production of methane (CH₄) and carbon dioxide (CO₂)” [34,35]. Note, “the production of methane (CH₄) and carbon dioxide (CO₂) from acetic acid (CH₃COOH) is an endothermic reaction process” that requires heat energy ($\mathrm{e}\mathrm{t}\mathrm{h}\mathrm{a}\mathrm{l}\mathrm{p}\mathrm{y} \mathrm{c}\mathrm{h}\mathrm{a}\mathrm{n}\mathrm{g}\mathrm{e}: ∆H^o=+$3.77 kcal/mol, equivalent to +15.8 kJ/mol) from the environment [17]:

$${CH}_{3}COOH\to {CH}_4+{CO}_2-3.77 \mathrm{k}\mathrm{c}\mathrm{a}\mathrm{l}/\mathrm{m}\mathrm{o}\mathrm{l}$$

(6)

As previously reported [3], “the methanogen’s anabolism, which utilizes acetic acid (CH₃COOH), mineral nutrients (N, P, K, Ca, Mg, S, Fe, Zn, Cu, Mo, etc.) under anaerobic conditions to synthesize cellular materials including sugar, lipids, proteins, and nucleotides for cell growth, also requires exogenous energy input from the environment. Since both its catabolic production of methane (CH₄) and carbon dioxide (CO₂) and its anabolism in synthesizing the cellular materials from acetic acid (CH₃COOH) are endothermic, the total metabolic process of Methanosarcina must thus be endothermic, requiring exogenous energy input. Consequently, based on the first law (conservation of mass and energy), the required energy input in this case must be from the isothermal utilization (absorption) of heat energy from the environment. This thus provides the thermodynamic first-law evidence for the existence of thermotrophic metabolism in the anaerobic methanogenic Methanosarcina cells”.

It is worthwhile to note that this thermodynamic first-law evidence for the existence of thermotrophic metabolism in anaerobic methanogenic Methanosarcina cells does not necessarily exclude the possibility for them still to be dual chemo-thermotrophs. Specifically, although its $∆H^o$ value is +15.8 kJ/mol, the entropy change for the production of methane (CH₄) and carbon dioxide (CO₂) from acetic acid (CH₃COOH) is still a substantial positive number ($∆S^o=+240 \mathrm{J}·{\mathrm{K}}^{-1}{·\mathrm{m}\mathrm{o}\mathrm{l}}^{-1})$; thus, the Gibbs free energy change in Equation (6) is a substantial negative number ($∆G^o=-55.2 \mathrm{k}\mathrm{J}·{\mathrm{m}\mathrm{o}\mathrm{l}}^{-1}; \mathrm{P}\mathrm{h}\mathrm{y}\mathrm{s}\mathrm{i}\mathrm{l}\mathrm{o}\mathrm{g}\mathrm{i}\mathrm{c}\mathrm{a}\mathrm{l} ∆G^{o\prime }=-36 \mathrm{k}\mathrm{J}·{\mathrm{m}\mathrm{o}\mathrm{l}}^{-1}$) [36]. That is, Methanosarcina may have a substantial “entropy-trophic” feature. On the other hand, all methanogens, to date, couple fermentation to the generation of a chemiosmotic transmembrane potential [37,38], which according to Equations (2)–(4) may be associated with TELPs and thus the TELP-enabled thermotrophic function (a Type-B energetic process).

5.2. Isothermal Heat Utilization in Anaerobic H₂-Producing and Acetic Acid-Producing Bacteria

An early analysis [17] indicated that “certain anaerobic H₂-producing bacteria [39,40] are also likely to carry the thermotrophic function capable of isothermally utilizing environmental heat energy, in a way similar to that of the methanogenic archaea Methanosarcina cells. For example, the anaerobic hydrogen-producing “S” bacteria can utilize ethanol (CH₃CH₂OH) to produce molecular dihydrogen (H₂) and acetic acid (CH₃COOH)” according to the following process reaction:

$${CH}_3{CH}_{2}OH+H_{2}O \to {CH}_{3}COOH+{2H}_2-19.16 \mathrm{k}\mathrm{c}\mathrm{a}\mathrm{l}/\mathrm{m}\mathrm{o}\mathrm{l}$$

(7)

This catabolic production of ${CH}_{3}COOH$ and $H_2$ from ${CH}_3{CH}_{2}OH$ (Equation (7)) is endothermic ($∆H^o=+$19.16 kcal/mol) [17]. The “S” bacteria anabolism, which anaerobically “utilizes ethanol (CH₃CH₂OH) and mineral nutrients (N, P, K, Ca, Mg, S, Fe, Zn, Cu, Mo) to synthesize cellular materials including sugar, lipids, proteins, and nucleotides for cell growth, also requires energy input”. Consequently, “based on the first law of thermodynamics, the anaerobic hydrogen producing “S” bacteria are also likely to carry thermotrophic function for isothermal utilization (absorption) of heat energy from the environment”. However, under certain syntrophic conditions [36], anaerobic H₂-producing and acetic acid-producing bacteria may still display substantial chemotrophic features through interspecies-coupled energy metabolism.

Similarly, “certain propanoic acid-utilizing, H₂-producing and acetic acid-producing bacteria anaerobically utilize propanoic acid (${CH}_3{CH}_{2}COOH$) to produce acetic acid (${CH}_{3}COOH$), hydrogen ($H_2$) and carbon dioxide (${CO}_2$)” according to the following process reaction:

$${CH}_3{CH}_{2}COOH+{2H}_{2}O \to {CH}_{3}COOH+{3H}_2+{CO}_2-48.93\mathrm{k}\mathrm{c}\mathrm{a}\mathrm{l}/\mathrm{m}\mathrm{o}\mathrm{l}$$

(8)

As previously analyzed [17], “the catabolic production of acetic acid, hydrogen and carbon dioxide from propanoic acid (Equation (8)) is clearly endothermic ($∆H^o=+$48.93 kcal/mol; $∆G^o=+13.59$ kcal/mol; $∆G^{o\prime }=+18.24$ kcal/mol); Their anabolism that anaerobically utilize propanoic acid (CH₃CH₂COOH) and mineral nutrients to synthesize cellular materials for cell growth certainly also requires additional energy input. Based on the thermodynamic first law, their required energy must be from the isothermal utilization (absorption) of heat energy from the environment. Therefore, this analysis result also indicated the existence of thermotrophic metabolism in the propanoic acid-utilizing, H₂-producing and acetic acid-producing bacteria”.

Furthermore, “certain butanoic acid-utilizing, H₂-producing and acetic acid-producing bacteria anaerobically utilize butanoic acid (${CH}_3{CH}_2{CH}_{2}COOH$) to produce acetic acid (${CH}_{3}COOH$) and hydrogen ($H_2$)” according to the following process reaction:

$${CH}_3{CH}_2{CH}_{2}COOH+{2H}_{2}O \to {2CH}_{3}COOH+{2H}_2-32.77 \mathrm{k}\mathrm{c}\mathrm{a}\mathrm{l}/\mathrm{m}\mathrm{o}\mathrm{l}$$

(9)

Accordingly, “the catabolic production of acetic acid, hydrogen and carbon dioxide from butanoic acid (Equation (9)) is clearly endothermic ($∆H^o=+$32.77 kcal/mol; $∆G^o=+16.13$ kcal/mol; $∆G^{o\prime }=+11.50$ kcal/mol) [17]; This analysis result indicated the existence of thermotrophic metabolism in the butanoic acid-utilizing, H₂-producing and acetic acid-producing bacteria” [3].

6. Experimental Evidence of Isothermal Absorption (Utilization) of Environmental Heat Energy in Methanosarcina

The predicted isothermal utilization (absorption) of environmental heat energy through thermotrophic metabolism is expected to lower the temperature in the liquid Methanosarcina cell culture. “This predicted isothermal utilization (absorption) of environmental heat energy by Methanosarcina was experimentally demonstrated”, as shown in the recently published report of Thermotrophy Exploratory Study [3]. Briefly, the Methanosarcina cells “were enriched from a liquid inoculum of a methane-producing anaerobic digestor using a minimal liquid culture medium containing acetate as the sole source of carbon under the anaerobic conditions”. The experimental observation demonstrated that “the metabolic activities in Methanosarcina liquid cell culture indeed resulted in a substantial temperature change (drop) by about −0.10 °C (and sometimes drop as much as −0.45 °C) compared with the control (liquid medium only without cells)”. This is noteworthy progress since it, “for the first time, experimentally demonstrated the isothermal absorption (utilization) of environmental heat energy owing to thermotrophy” [3].

7. Thermotrophy-Associated Protonic Bioenergetic Systems as Type-B Energetic Processes Widely Operate in Natural Environments

It is now also clear that the Type-B thermotrophic process associated with TELPs has occurred for billions of years already in the biosphere on Earth. All organisms including bacteria, fungi, algae, higher plants, and mitochondria-powered animals have chemiosmotic transmembrane potential that is associated with TELPs (Equations (2)–(4)). The “intimate relationship between the ideal TELP concentration ${\left[H_L^{+}\right]}^0$ and transmembrane potential difference $∆\psi$ is described in the TELP equation (Equation (3)), which shows that as long as there is a substantial value of $∆\psi$, there must be TELPs” [10]. This relationship is also true for vice versa. Therefore, TELPs and $∆\psi$ represent the “two faces” of a protonic capacitor [5,41]. As reported previously [10], fundamentally, it is “the formation of a TELP-associated membrane capacitor that gives rise to $∆\psi$”, as shown in the following transmembrane potential equation:

$$∆\psi =\frac{S·l·F·{\left[H_L^{+}\right]}^0}{C}=\frac{S·l·F·(\left[H_L^{+}\right]+\sum _{i=1}^n\left[M_L^{i+}\right])}{C}$$

(10)

On the other hand, “the presence of $∆\psi$ must indicate the presence of TELPs ($\left[H_L^{+}\right]$)” [5,10,41], which is the source of the local pmf energy (Equation (2)) that isothermally utilizes environmental heat energy.

Therefore, TELP thermotrophy (Type-B energetic process) widely operates in all organisms everywhere in the biosphere on Earth today, including the vast lands of crops and animals, mountains of forests, birds in the skies, and all the known organisms in soils, ponds, lakes, rivers, and seas. Therefore, we have now “identified two thermodynamically distinct types (A and B) of energy processes naturally occurring on Earth, based on their properties of whether they follow the second law of thermodynamics or not” [4]. As mentioned before, Type-A energetic processes such as classic heat engines, and many of the known chemical reactions and processes in our test tubes, computers, and cars, apparently well follow the second law; “Type-B energetic processes represented by the thermotrophic function (Figure 1, Figure 2 and Figure 3) here do not have to be constrained by the second law, owing to the special asymmetric function” [4]. That is, the second law remains still to be an incredibly good law. However, it does not necessarily have to always be universal as also implied by several independent studies [17,42,43,44,45,46,47,48,49,50,51,52,53].

We now “have, at least, three well-defined biosystems, mitochondria [2], alkalophilic bacteria [1], and methanogen Methanosarcina [3] with well-corroborated scientific evidences showing a special Type-B process that perfectly follows the thermodynamic first law (conservation of mass and energy), but is not constrained by the second law of thermodynamics”. As shown in Equation (5), the TELP formation entropy change ($∆S_{LF}$) for the TELP-associated isothermal environmental heat utilization was calculated indeed to be a negative number.

Therefore, the new understanding of the Type-B process may “represent a complementary development to the second law of thermodynamics and its applicability in bettering the science of bioenergetics and energy renewal” [25]. In addition to naturally occurring Type-B energetic processes, a number of Type-B energetic processes have now been created by human efforts, as briefly presented in the following sections.

8. Asymmetric Function-Gated Isothermal Electricity Production

Figure 4 presents an invention [51] of “an integrated isothermal electricity generator system 1300 that comprises multiple pairs of emitters and collectors working in series. The system 1300 comprises four parallel electric conductor plates 1301, 1302, 1321 and 1332 set apart with barrier spaces (such as vacuum spaces) 1304, 1324, and 1334 in between the conductor plates. Accordingly, the first electric conductive plate 1301 has its right side surface coated with a thin layer of low work function (LWF) film 1303 serving as the first emitter; The second electric conductive plate 1302 has its left side surface coated with a thin layer of high work function (HWF) film 1309 serving as the first collector while its right side surface coated with a thin layer of low work function (LWF) film 1323 serving as the second emitter; The third electric conductive plate 1321 has its left side surface coated with a thin layer of high work function (HWF) film 1329 serving as the second collector while its right side surface coated with a thin layer of low work function (LWF) film 1333 serving as the third emitter; The fourth electric conductive plate 1332 has its left side surface coated with a thin layer of high work function (HWF) film 1339 serving as third (terminal) collector; The first barrier space 1304 allows the thermal electron flow 1305 to pass through ballistically between the first pair of emitter 1303 and collector 1309; The second barrier space 1324 allows the thermal electron flow 1325 to pass through ballistically between the second pair of emitter 1323 and collector 1329; The third barrier space 1334 allows the thermal electron flow 1335 to pass through ballistically between the third pair of emitter 1333 and collector 1339” [54].

It is a preferred practice to employ the following: “a first capacitor 1361 connected in between the first and second electric conductor plates 1301 and 1302; a second capacitor 1362 linked in between the second and third conductor plates 1302 and 1321; a third capacitor 1363 used in between third and the fourth conductor plates 1321 and 1332 as illustrated in Figure 4. The use of capacitors in this manner can typically provide better system stability and robust isothermal electricity delivery. In this example with the first conductor plate 1301 grounded, isothermal electricity can be delivered through outlet terminals 1306 and 1376 or 1377 depending on the specific output power needs. When the isothermal electricity is delivered through outlet terminals 1306 and 1376 across a pair of emitter and collector, the steady-state operating output voltage equals to V(c), which typically can be around 3~4 V depending on the system operating conditions including the load resistance and the difference in work function between the emitter and the collector. When the isothermal electricity is delivered through outlet terminals 1306 and 1377 across three pairs of emitters and collectors, the steady-state operating output voltage is 3 × Vc, which typically can be about 9~12 V in this example” [54].

The isothermal electricity of the 1300 system (Figure 4) “can be delivered also through outlet terminals1376 and 1377. In this case, the V(c) voltage at the second electric conductor plate 1302 generated by the activity of the first emitter (conductor 1301 with LWF film 1303) and first collector (HWF plate 1309) may serve as a bias voltage for the second emitter (LWF film 1323 on the right side surface of the second electric conductor plate 1302) so that the second emitter 1323 will more readily emit thermal electrons towards the second collector 1329 on the left side surface of the third conductor plate 1321 which has the third emitter 1333. Subsequently, the V(c) created at the second collector 1329 of the third conductor plate 1321 can serve as a bias voltage for the third emitter 1333 to emit thermal electrons more readily towards the terminal collector 1339 at the fourth conductor plate 1332 to facilitate the generation of isothermal electricity for delivery through the outlet terminals 1376 and 1377. Therefore, use of this special feature can help better extract environmental energy especially when the operating environmental temperature is relatively low or when the work function of certain emitters alone may not be entirely low enough to function effectively. When the isothermal electricity is delivered through the outlet terminals 1376 and 1377, the steady-state operating output voltage is 2 × Vc, which typically can be about 6~8 V” [54].

For a typical electron emitter, its emitted current density, J, is given by the Richardson–Dushman equation [55,56,57], J = AT²exp(−W/kT), i.e.,

$$J=A{T}^2{ e}^{-W/kT}$$

(11)

where T is the thermodynamic temperature of the emitter, W is its work function, k is the Boltzmann constant, and A is a constant.

For an asymmetric function-gated thermal electron power generator system 1300 as illustrated in Figure 4 that “operates isothermally, the temperature at the emitter ($T_e$) equals to that of the collector ($T_c$). Under the isothermal operating conditions ($T=T_e=T_c)$, the ideal net flow density (flux) of the emitted electrons 1105 from the emitter 1101 to the collector 1102, which is defined also as the ideal isothermal electron flux ($J_{isoT}$) normal to the surfaces of the emitter and collector can be calculated based on the application of Richardson-Dushman formulation (Equation 11) in the following ideal isothermal current density ($J_{isoT}$) equation:

$$J_{isoT}=A{T}^2{(e}^{-[WF\left(e\right)+e · V\left(e\right)]/kT} - e^{-[WF\left(c\right)+e · V\left(c\right)]/kT})$$

(12)

where $A$ is the universal factor (as known as the Richardson-Dushman constant) which can be expressed as $\frac{4\pi me{k}^2}{h^3}\approx 120\mathrm{A}\mathrm{m}\mathrm{p}/({\mathrm{K}}^2.{\mathrm{c}\mathrm{m}}^2)$ [where $m$ is the electron mass, $e$ is the electron unit charge,$k$ is the Boltzmann constant and $h$ is Planck constant]. $T$ is the absolute temperature in Kelvin (K) for both the emitter and the collector; $WF\left(e\right)$ is the work function of the emitter surface; the term of $e·V\left(e\right)$ is the product of the electron unit charge $e$ and the voltage $V\left(e\right)$ at the emitter; specially note, the k here is the Boltzmann constant in (eV/K); $WF\left(c\right)$ is the work function of the collector surface; and $e·V\left(c\right)$ is the product of the electron unit charge $e$ and the voltage $V\left(c\right)$ at the collector” [4].

When the voltage at the emitter ($V\left(e\right)$) is zero such as when the emitter is grounded as illustrated in Figure 4, “the ideal net isothermal electrons flow density across the vacuum space from the emitter 1101 to the collector 1102 can be calculated using the following modified ideal isothermal current density ($J_{isoT\left(gnd\right)}$) equation” [54]:

$$J_{isoT\left(gnd\right)}=A{T}^2{(e}^{-\left[WF\left(e\right)\right]/kT} - e^{-[WF\left(c\right)+e · V\left(c\right)]/kT})$$

(13)

When the voltage at both the emitter ($V\left(e\right)$) and the collector ($V\left(c\right)$) are zero such as at the initial state of an isothermal electricity generation system, “the maximum net isothermal electron flow density across the vacuum space from the emitter 1101 to the collector 1102 reaches the highest attainable, which is regarded as the ‘saturation’ (upper limit) flux”. This “ideal saturation electron flux” can be calculated using the following ideal saturation isothermal current density ($J_{isoT\left(sat\right)}$) equation [54]:

$$J_{isoT\left(sat\right)}=A{T}^2{(e}^{-\left[WF\left(e\right)\right]/kT} - e^{-\left[WF\left(c\right)\right]/kT})$$

(14)

Note, Equation (14) shows that the ideal saturation electron flux is the emitter’s emitted current density, J_e, (which is expressed by the Richardson–Dushman equation) minus the collector’s emitted current density, J_c, (which is also expressed by the Richardson–Dushman equation). This explains how the Richardson–Dushman equation (11) was applied in Equations (12)–(14) that scientifically show the fundamental mechanism for the asymmetric function-gated continuous isothermal direct current (DC) electricity power production through utilization of environmental heat energy without requiring any temperature gradient between the emitter and collector [54].

Figure 5 presents “the ideal isothermal electricity current density (A/cm²) curves as a function of output voltage V(c) from 0.00 to 4.10 V at operating environmental temperature of 273, 293, 298, and 303 K for a pair of emitter work function (WF(e) = 0.50 eV) and collector work function (WF(c) = 4.60 eV, graphene and/or graphite) with the emitter grounded. These curves show that the isothermal electron current density is pretty much constant (steady) in a range of output voltage V(c) from 0.00 to 4.00 V at each of the operating environmental temperature of 273, 293, 298, and 303 K. Only when the output voltage V(c) is raised beyond 4.00 V up to the limit of 4.10 V, the isothermal electron current density is dramatically reduced to zero. The level of the steady-state isothermal electron current density at an output voltage of 3.50 V increases dramatically with temperature from 5.26 × 10⁻³ A/cm² at 273 K (0 °C) to 2.59 × 10⁻² A/cm² at 293 K (20 °C), 3.73 × 10⁻² A/cm² at 298 K (25 °C), and to 5.32 × 10⁻² A/cm² at 303 K (30 °C)” [54].

More evidence and scientific support for the disclosed invention (Type-B energetic process) are not only the computed numerical data of the isothermal electron current density (Figure 5) but also the isothermal electron current density ($J_{isoT\left(sat\right)}$) equation (Equation (14)) per se where the isothermal environmental heat utilization is inherently embedded with the “$kT$” thermal term, based on well-established physical sciences. The physical equation (Equation (14)) also shows that asymmetric function-gated isothermal electricity generators can produce isothermal electricity as long as the electron work function [WF(e)] of the emitter is substantially lower than that of the collector [WF(c)]. Furthermore, sustainable isothermal electricity production has already been experimentally demonstrated through a prototype of an asymmetric function-gated isothermal electron-based environmental heat energy utilization system (see PCT International Patent Application Publication WO 2019/136037 A1: paragraphs 0097–0103, experimental data listed in its Table 7, paragraphs 0172–0190, and experimental data in its Table 10 and Table 11 as shown in Ref. [49]).

9. Epicatalysis Generating a Temperature Difference between Catalysis-Asymmetric Filaments

In experimental tests of Duncan’s paradox [58], Sheehan et al. [46] experimentally demonstrated that epicatalysis can generate a temperature difference between catalysis-asymmetric filaments (Figure 6). The experiment employed molecular hydrogen H₂ dissociation (H₂ → 2H) on rhenium (Re) and tungsten (W) filaments at high temperature. In the high-temperature hydrogen/W/Re blackbody cavity experiment, large steady-state temperature differences (∆T ≥ 120 K) were observed, and consequently, power production densities of roughly 10⁴ Watts/m² were inferred [46]. Therefore, this experimental result may represent a clear demonstration of a human-created Type-B energetic process.

10. Artificially Made Asymmetric Membrane Concentration Cell

Sheehan et al. [59] recently created an asymmetric membrane concentration cell which charges using a unique mechanism of isothermally utilizing environmental heat energy: “its concentration difference is generated internally by a chemically-asymmetric membrane that drives anisotropic diffusion of electrolyte ions, rather than being provided by an external source”. They experimentally demonstrated an asymmetric membrane separator-generated ΔpH of 0.04, which was converted to electron motive force and current (5 × 10⁻³ V, ∼10⁻⁶ A), resulting in a power generation of 5 × 10⁻⁹ W. Sheehan’s analysis [60] indicated that asymmetric membrane separator-generated ΔpHs ∼ 1–2 should be attainable, corresponding to concentration ratios of 10–100, which can be utilized to generate an electric power density of more than 10⁷ W/m³. The experimental results [59] agree well with theoretical predictions [60], which represent another example of a human-created Type-B energetic process.

11. Fu’s Experiment on Heat–Electric Conversion Using Surface Electron Emission under a Static Magnetic Field

As recently reported [61], Fu’s experiment employed a vacuum tube containing two identical and coplanar Ag-O-Cs surfaces separated by a mica insulator (Figure 7). The two Ag-O-Cs surfaces served as emitters A and B (work function 0.8 eV) that ceaselessly emitted thermal electrons at room temperature. The trajectory of the emitted electrons was controlled (bent) by the use of a static uniform magnetic field so that the number of electrons migrating from A to B exceeded that from B to A (or vice versa). The net migration of thermal electrons from A to B quickly resulted in a charge distribution of A charged positively and B negatively. Consequently, a voltage difference between A and B emerged, enabling a continuous output electron current (power) through an external load.

Figure 8 presents the continuous output current (I) experimentally measured from Fu’s electrotube FX12-51 at various static uniform magnetic fields B at a room temperature of 22 °C [61]. The data showed the continuous output current (I) at a static magnetic field range from −15 to 15 gauss. At the static magnetic field of 2.7 gauss, the measured continuous output current (I) reached as high as 180 fA. Therefore, this experimental result may also represent another clear demonstration of a Type-B energetic process that isothermally utilizes environmental heat energy to produce electricity.

Notably, Fu’s finding of heat–electric conversion using surface electron emission under a static magnetic field [61] that he repeatedly demonstrated through his pioneering work of more than 40 years since the 1980s [62,63,64] was recently also independently demonstrated by the work of Perminov and Nikulov [65] who in 2011 were apparently unaware of Prof. Fu’s pioneering work in the field. Therefore, the validity of Fu’s discovery on heat–electric conversion using surface electron emission under a static magnetic field [66,67,68,69,70] was proven well beyond any reasonable doubt. Therefore, it is now classified as a human-created Type-B energetic process.

12. Dynamic Processes in Superconductors Indicating Type-B Energetic Process

The observations of the DC voltage on an asymmetric superconducting ring testify that one of the ring segments is a DC power source [66]. According to Nikulov and his associates, “the persistent current flows against the total electric field in this segment. This paradoxical phenomenon is observed when the ring or its segments are switched between superconducting and normal state by non-equilibrium noises”. It was demonstrated that “the DC voltage and the power increase with the number of identical rings connected in series. Large voltage and power sufficient for practical application can be obtained in a system with a sufficiently large number of the rings”. This points to “the possibility of using such a system for the observation of DC voltage in the normal state of superconducting rings and in asymmetric rings made of normal metal” [66].

Furthermore, according to Nikulov’s analysis [67], the Meissner effect generating a persistent (perpetual) current in certain superconductors apparently contradicts with the law of entropy increase (the second law), especially when the annihilation of an electric current in normal metal with the generation of Joule heat is considered [68]. That is, the phenomenon of superconductors may indicate kinds of Type-B energetic process characteristics.

13. Type-B Energetic Processes: The Second Law of Thermodynamics Does Not Necessarily Have to Be Universal

The identification of Type-B energy processes shows that there is an entirely new world of physics, chemistry, and biochemistry yet to be fully explored.

We all understand that “the second law remains still as an incredibly good law. However, it does not necessarily have to be always absolute or universal”, as also implied by other well-documented independent studies [17,42,43,44,45,46,47,48,49,50,51,52,53,69]. The special Type-B process perfectly follows the first law (conservation of mass and energy) of thermodynamics but does not obey the second law of thermodynamics. In other words, the TELP-associated thermotrophic function as a Type-B process clearly represents an example of a natural “second law violation” since the Type-B process by its definition is not constrained by the second law.

Note, the second law of thermodynamics was developed from the Sadi Carnot cycle [70] that was based on the ideal gas law (nRT = PV; here, P is pressure, V is volume, and n is the number of moles) where the ideal molecular particles were assumed to have freedom in a 3-dimensional space (volume) without the consideration of any asymmetric structures. In the case of protonic bioenergetic systems, the TELPs are on a 2-dimensional membrane surface with asymmetric properties, “which is quite different from the assumed 3-dimensional space (volume) system that the second law was based on” [25]. Therefore, one must be careful not to mindlessly apply something like the second law derived from a three-dimensional space (volume) system to a two-dimensional and/or one-dimensional system without looking into the specific facts.

Furthermore, thermodynamic–spatial asymmetric features that may be “human-made” [4,46,71] and/or “have resulted from the billion years of natural evolution were not considered by the formulation of the second law per se”; this is another reason that one “shall be careful not to mindlessly or blindly apply the second law with monolithic thinking to certain special cases involving asymmetric systems without looking into the specifics” [25].

That is, “the second law can be well applied to the Type-A processes such as classical heat engines, and many of the known chemical, electrical, and mechanical processes where the second law belongs; The second law should not be blindly applied to Type B energy processes owing to their special asymmetric functions. It is important now for our scientific communities to avoid monolithic thinking and keep an open mind to consider the Type-B processes and their related phenomena in certain physical, chemical, and/or biological processes especially where asymmetric mechanisms are involved. The scientific communities may well benefit from the new fundamental understanding of Type-B processes uncovered in the natural Earth environment. To avoid the blind faith in the second law, the scientific community must pay attention to what this law was really based on and to better understand its limitations that are of great scientific and practical importance” [25].

14. Directions for Future Research and Education

14.1. Better Messaging and Education on Type-B Energetic Processes

Currently, we already know the existence of Type-B energetic processes on Earth such as naturally occurring TELP thermotrophic properties in life with quite clear scientific evidence [1,2,3,5]. As mentioned above, a number of groundbreaking human-made Type-B energetic processes including (but not limited to) “asymmetric function-gated isothermal electricity production” [51,54], “epicatalysis generating a temperature difference between catalysis-asymmetric filaments” [46], “artificially-made asymmetric membrane concentration cell” [59,60], “Fu’s experiment on heat-electric conversion using surface electron emission under a static magnetic field” [61], and the “dynamic processes in superconductors indicating Type-B energetic process” [66,67,68] have been invented and/or experimentally demonstrated. However, currently, almost the entire scientific community and the public are “still in sleeping with all the Type-A energetic processes taught in textbooks”; only a quite limited number of scientists now understand and appreciate Type-B energetic processes. Therefore, better messaging and education on Type-B energetic processes are highly needed to achieve the mission.

Currently, large parts of the scientific community including numerous program directors and panelists in many funding agencies such as the U.S. Department of Energy, the National Science Foundation, and the National Institute of Health are probably still unaware of Type-B energetic processes. Therefore, it is critically important to educate the scientific community including program managers about newly identified Type-B energetic processes, especially since some of the funding agencies might still have the old written and/or unwritten rule of “not to fund any anti-second law project”. Similarly, many patent examiners including (but not limited to) those at the United States Patent and Trademark Office may or may not be able to quickly understand and appreciate inventions on Type-B energetic processes. For example, it would not be entirely surprising for some examiners to refuse to understand and accept asymmetric function-gated electron current production equations (such as Equations (12)–(14)) and the associated data (like that of Figure 5) that are now quite clear to us. Since some of them could be so fixated with the textbook concept of “the law of degradation of energy (the second law)”, even in front of a live experimental demonstration for a valid invention on a Type-B energetic process like the asymmetric function-gated isothermal electricity production, they still might not believe what they see and try to invoke something completely irrelevant like the known “contact potential difference” mechanism to argue. The commercialization of Type-B energy technologies requires patent-protected IPs. Here, we again see the imperative of outreach and public education on Type-B energetic processes.

14.2. The Search for More Type-B Energetic Processes in the Natural World

So far, we understand that TELPs and their associated isothermal utilization of environmental heat in combination with the asymmetric membrane structures and functions are critically important, which represents a Type-B energetic process in natural biological systems. Are there any other processes that may also have a Type-B energetic feature? Certain asymmetric catalysis in enzymes may be a new area of interest for search and examination to identify new Type-B energetic features. For example, all 20 natural amino acids are made exclusively in their L configuration through certain asymmetric catalysis in the enzymes of their synthesis pathways. This type of asymmetric catalysis may contain certain characteristics of a Type-B process important to life.

14.3. Further In-Depth Studies on Type-B Energetic Processes

We now begin to understand Type-B energetic processes, which typically require a type of asymmetric structure and/or function. More in-depth studies are needed to better understand Type-B energetic processes and their applications. For example, more efforts are needed to investigate potential applications in quantum computing and nanotechnology and to develop theoretical frameworks integrating asymmetric functions and thermodynamics. There is also a need to conduct experimental validations across various scales and conditions and analyze implications for existing thermodynamic models and laws.

14.4. The Application of the Type-B Energetic Concept to Better Understand the Universe

The question of how the universe and its black holes operate is a fascinating topic that intrigues many scholars and the public across the world [72,73,74]. A black hole is a region of spacetime where gravity is so strong that nothing, including light and other electromagnetic waves, is capable of possessing enough energy to escape it [75,76]. The existence of black holes in the universe is now a well-established scientific fact [77,78]. Based on my analysis with the Type-B energetic concept, the universe may comprise both Type-A and Type-B energetic processes. The Big Bang and many of the associated physical and chemistry processes with freedoms in 3D spaces could thus be well described by the second law of thermodynamics, which may represent Type-A energetic processes with positive entropy changes. On the other hand, a black hole formation and growing process that takes matter (mass and energy) into the black hole’s single center point (singularity) may represent a Type-B energetic process with events of negative entropy changes. When many supermassive blackholes finally merge, forming a giant supermassive blackhole with a singularity point, it may then somehow trigger another big bang. In this way, the universe may cycle endlessly between “big bang” (Type-A energetic process) and “black hole formation” (Type-B energetic process). More research efforts are needed to better understand the universe and black holes with the Type-B energetic concept.

15. Concluding Remarks

It is now quite clear that many of the recent scientific explorations in regard to the second law of thermodynamics such as the recent studies of Sheehan et al. [43,46,79], Fu [61,62,63,64], and Nikulov [66,67,68] are really legitimate and thus should be encouraged to move the field forward. In hindsight, however, some of the language used in the past such as “challenging the second law of thermodynamics” [43,80,81,82] appears to be somewhat inaccurate or did not seem to carry the right messages for the scientific community. It could in part explain why the messages so far still have not been well received by many in the scientific community, who may feel the second law is serving their research very well for good reasons. In fact, to many in the scientific community who may be familiar only with Type-A processes, the term “challenging the second law of thermodynamics” could be misunderstood as “challenging” their career establishment that might have been built on the classic thermodynamic second law as taught in textbooks. Consequently, some of them may feel “totally upset” or “annoyed” with “total disbelief,” quite often tending to completely ignore or reject the topic of discussions. Therefore, this author encourages the use of some more accurate terms like “challenging the applicability (or universality) of the thermodynamic second law,” since the second law is applicable to Type-A processes but may not necessarily be applicable to Type-B processes because of their special asymmetric functions.

For the modern world in which the second law is now known to be not absolute, Type-B processes may be harnessed “to do useful work such as generating isothermal electricity to power the modern electricity-based world economy” [54]. For example, “a novel invention on isothermal electricity for energy renewal (WO 2019/136037 A1) has now been made to generate isothermal electricity by innovatively translating the concept of the asymmetric protonic membrane capacitor-enabled Type-B process into an isothermal electron-based power generation system”, which could be made into a chip device [51]. “Its isothermal electricity power density could be so surprisingly good that its chip with a size of about 40 cm² may be sufficient to continuously power a smart mobile phone device forever” [4,54]. That is, based on the invention [51], novel Type-B energy technologies such as asymmetric function-gated isothermal electricity generator systems have the potential for use to permanently power many electric devices, electric motors, machines, and vehicles including (but not limited to) mobile phones, laptops, cars, buses, trains, ships, and airplanes utilizing the limitless environmental heat energy alone without requiring any fossil fuel energy [4,54]. Therefore, innovative scientific research, development, and commercialization efforts in mimicking and/or creating Type-B processes [4] to isothermally utilize the endless environmental heat energy [4,46,51,66,71] should be highly encouraged to “help ultimately liberate all peoples from their dependence of fossil fuel energy, thus helping to reduce greenhouse gas CO₂ emissions and control climate change towards a common shared sustainable future for the humanity on Earth” [54]. In addition to the needed support for further research, development, and commercialization efforts, currently, better messaging and education on Type-B energetic processes are also highly needed to achieve the mission.