Thermoelectric Harvesting Using Warm-Blooded Animals in Wildlife Tracking Applications^†

Round 1

Reviewer 1 Report

Animal fur is different, even from goats or sheeps. More studies must be carried out in different climate conditions, including hot summer, when environmental temperature could be higher than animal one.

Humidity must be also considered and the behaviour of that device in water is another major issue.

Overall, it is a very ingenious study! Congratulation to the team!

Author Response

We would like to thank the reviewer for the
thoughtful comments and efforts towards improving our manuscript.

In fact, the reviewer is right that different environmental conditions heavily influence the thermal properties of the fur. Our setup however covers only a small portion of the possible variables and can be seen as a staring point, showing that there is a chance significant improvements for thermal harvesting at the body of an animal. More studies are here the key, as the reviewer writes. We are going to express this in the next revision.

Reviewer 2 Report

This paper deals with the optimization of the structure of the thermoelectric harvesting system for animals. The different structure of the thermal heat connector (THC) at the interface of the fur of goat and sheep was tested to evaluate their thermal resistance. The optimized design reduced the thermal resistance by 38% by lowering its weight. Yet, the authors only investigated the cylindrical structure with five different diameters and spacing, including reference. I wonder this limited parameter is not enough to optimize this device entirely. How does the length or materials of the fins will affect the result? Heat transfer simulation is one of the choices to optimize the geometry of THC.

 

Minor comment

(1) Please spell out TEG when it first appears in the main text.

(2) Please indicate why fur of goat and sheep were used? Is this an appropriate test model for wildlife monitoring?

Author Response

We would like to thank the reviewer for the
thoughtful comments and efforts towards improving our manuscript.

The design parameters of the thermal heat connector are based on those of commercially available heat sinks. These devices are well understood and the heat transfer of those is modeled and simulated routinely. Therefore, the impact of parameters such as fin diameter, spacing, length and material could indeed be computed if the environmental boundaries are well known. However, we are facing the challenge that the behavior of the environment, here the fur, is not understood completely when interacting with the THC. Indeed, as the reviewer states, the chosen parameters in our setup may not cover the necessary search space for an optimal design. This will be left for further investigations and we are currently working on an appropriate heat transfer simulation that takes the behavior of the fur – we saw in this paper - into account.

Reviewer 3 Report

The authors report on the thermal harvesting system mounted at endothermic animals based on thermoelectric power generation. In the paper, the design of an optimized thermal interface has been proposed. The research is well-conducted with both calculation and experiment. The results are clearly presented, which are informative for readers. Therefore, I would like to recommend this paper to be published after text editing.

Author Response

We would like to thank the reviewer for the
thoughtful comments and efforts towards improving our manuscript.

Reviewer 4 Report

In the paper a device very useful to tracking the warm-blooded animals is studied from the electric supply point of view. I suggest the publication with the minor revisions reported below:

1) Which is the weight of the proposed apparatus? Infact, this apparatus should be present togheter a classical electrical supply for the GPS

2) Have the authors conduct a cost/benfits study because of the device alone isn't capable to feed the GPS in any case? The cost of the proposed device to decrease the thermal resistance doesn't seems negligible.

 

Author Response

We would like to thank the reviewer for the
thoughtful comments and efforts towards improving our manuscript.

(1) This is a valid point. We are going to add additional information about the weight of commercially available battery driven trackers. In our presented approach, the greatest part of weight will be the thermal-heat-connector, together with a fitting heat sink. Both parts likely will weight around 50 grams.

(2) There are no studies about the costs done yet, but we are currently preparing a real field experiment with such a system, including GPS to gather data about the feasibility.