This appendix explains the details about the game so that readers can have a clearer image of it. As the purpose of the article is not to offer instructions on how to play the game itself, explaining the full detail of the game is avoided. The authors are pleased to offer the complete information necessary to play the latest version of the game upon request.
Appendix A.1. Items Used in the Game
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Power generation facility card
In this game, a power generation facility is represented by a card, as shown in
Figure A1. The front of the card shows the type and level of the power generation facility, the price, the amount of power it can generate, and the amount of greenhouse gas emissions. The level of a facility generally ranges from one to three, in which the higher the level, the larger the output of the facility. There is no Level 1 nuclear power; wind and solar powers have only Level 2. The players purchase power generation facility cards during the game; they can own as many power generation facility cards as long as they can afford; however, the number of cards in the game is limited.
There are seven types of power generation facilities, as summarized in
Table 1. Coal-, oil-, and gas-fired power generation facilities require resources to generate power, and their outputs are proportional to the amounts of resource inputs. Whereas nuclear power also requires resources to generate power, its output and the amount of resources needed for power generation are constant. The amounts of electricity generated by wind and solar power are determined by the rolled dice in every round. The number of dice rolled is one for wind and two for solar, regardless of the number of cards. That is, a player having three Level 2 wind power cards rolls one die and multiplies the results by 0.6 (=0.2 × 3) to decide the amount of power to be generated.
The prices of power generation facilities are basically based on the recent levelized cost of electricity in Japan. Specifically, the price of Level 3 nuclear power, which can generate 12 TWh, is set to JPY 600 billion. The prices of other facilities are decided based on their corresponding outputs and the ratios of their initial costs with those of nuclear power in the levelized cost. The price of gas-fired power generation facilities is adjusted to make them more expensive, while those of solar and wind power are cheaper than the actual ones to balance the game. More specific information on the facilities is summarized in
Table A1 and
Table A2.
Figure A1.
Examples of power generation facility cards.
Figure A1.
Examples of power generation facility cards.
Table A1.
Maximum output of power generation facilities (unit: TWh).
Table A1.
Maximum output of power generation facilities (unit: TWh).
| Level 1 | Level 2 | Level 3 |
---|
Coal-fired *1 | 4 | 8 | 12 |
Oil-fired *1 | 4 | 8 | 12 |
Gas-fired *1 | 4 | 8 | 12 |
Nuclear *1 | N/A | 8 | 12 |
Hydropower | 2 | 4 | 6 |
Solar | N/A | 1.2 *2 | N/A |
Wind | N/A | 1.2 *3 | N/A |
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Dice (four colors × 20 for representing the resources + another color × 4–8 for random number generation)
The four colored dice are used to represent the four resources, respectively, and the other dice are used to generate various random numbers. For the dice representing resources, the color of the dice represents the type of resource they represent (blue: coal, red: oil, purple: gas, yellow: uranium), and the eye of the dice represents the amount of resources. The price of a resource, shown on the mainboard, is the price of one die, and it is independent from the eye. Thus, dice with six eyes and dice with one eye are six times different in value. The prices of the resources and their fluctuations are based on the actual fuel and other operation costs in the levelized cost of electricity in Japan and the change in the spot prices of the resource in the last several decades.
Table A2.
Price of power generation facilities (unit: billion JPY).
Table A2.
Price of power generation facilities (unit: billion JPY).
| Level 1 | Level 2 | Level 3 |
---|
Coal-fired *1 | 80 | 160 | 240 |
Oil-fired *1 | 100 | 200 | 300 |
Gas-fired *1 | 90 | 150 | 200 |
Nuclear *1 | N/A | 400 | 600 |
Hydropower | 100 | 200 | 300 |
Solar | N/A | 100 *1 | N/A |
Wind | N/A | 90 *2 | N/A |
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Mainboard
The mainboard, shown in
Figure A2, is an A3-sized sheet placed at the center of the field during the game. It is to clearly show important information: the number of rounds in the game, each player’s development level, power requirements, the maximum fuel (number of dice) one can possess, GHG emission limits, resource prices, and the order of purchases for that round.
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Investment card
An investment card can be obtained at the auction held in each round and has various positive effects, as presented in
Figure A3. Some cards are useful for interfering with other players’ strategies. For example, the “global warming countermeasure” card can decrease all players’ GHG limits by 50 or 100, while the “tightening of regulation” card can remove up to four power generation facility cards from the field. Some cards provide additional scores at the end of the game.
Figure A3.
Example of an investment card.
Figure A3.
Example of an investment card.
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Event card
Event cards are used for triggering events. There are ten event cards for each round, namely 10 × 3 = 30 cards. Most events provide either a positive or negative effect on a specific power generation facility or resource, such as increase or decrease in the price of oil. One of most important event cards is the “nuclear accident” shown in
Figure A4. This card appears in the third round with a probability of 75%. When this card appears, two dice are rolled to evaluate whether something serious will happen. If their eyes are both one (thus about once in 50 games), all players must discard all the nuclear power facility cards they possess and are required to pay equal to the sum of the prices of the cards. Players with “nuclear safety measure” investment cards can reduce this possibility to 1/6 per card. That is, a player with two nuclear safety measure investment cards can evade this effect unless the eyes of an additional two dice rolls are both one (a probability of about once in 1800 games, which would be negligibly small for a player). The players are given an overview of possible events, including the nuclear accident, prior to the start of the game.
Figure A4.
Example of an event card (“nuclear accident” card).
Figure A4.
Example of an event card (“nuclear accident” card).
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Chips and debt cards
Chips confirm the funds owned by each player. The authors used ordinary casino chips, but any chips or even other items may be used if they can represent up to JPY 1 trillion with a minimum unit of JPY 5 billion. Debt cards, shown in
Figure A5, show a player’s debt, which can be paid in JPY 100 billion increments at any time in the game. When borrowing money, a player receives a JPY 100 billion debt card and JPY 50 billion in cash at the same time (100% interest is accrued immediately).
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Rule card
The rule card, shown in
Figure A6, is an A5-size document with a summary of what to do on each round on the front and supplementary rules on the back. One copy is given to each player.
Appendix A.2. Procedure
Prior to the start of the game, players perform the following to prepare for the game:
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Each player receives one card for each of the following power facility cards: Level 1 coal-fired power, Level 1 oil-fired power, Level 1 gas-fired power, and Level 1 hydropower;
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The remaining power generation facility, investment, and event cards for each round are individually shuffled to create five piles;
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Eight power generation facility cards are drawn from the pile to finally line up eight types of (not eight) power generation facility cards in the field;
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The mainboard is placed at the center of the field. A die is rolled four times to determine the prices of the coal, oil, gas, and uranium for the first round, and marks are placed at the fuel price table of the mainboard according to the rolled die;
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Six dice for each color are arranged in the field to represent the resources. The eyes are random;
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Players place their pieces at the “GHG limit” row of the main board to indicate that their GHG emission limit is 600;
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Players determine the purchase order for the first round according to the dice roll (the highest roll goes first). Each player’s pieces are placed in the purchase order at the top of the mainboard. The 1st/2nd/3rd/4th players in the order of purchase receive JPY 500/520/540/560 billion, respectively;
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Players decide the development level in the first round from 1 to 4 and then place their pieces on the line of the corresponding development level on the left side of the mainboard. Those who chose Levels 1 and 2 increase their GHG limit by 200 and 50, respectively; they move their pieces to the “GHG limit” row to represent this.
Subsequently, the players start the game. “One round” of the game consists of the following nine phases. An overview of what players do in the phases is described below.
Appendix A.2.1. Phase 1: Investment
Six investment cards are drawn from the pile and placed on the field. Players auction them until there is no card in the field, or there are no more cards any player wants to buy. All unsold cards are discarded. There is no limitation on the number of investment cards a player can obtain or possess.
Appendix A.2.2. Phase 2: Purchasing Power Generation Facility
Players purchase power generation facilities on the field one by one (multiple purchases cannot be made at the same time) in the order shown on the mainboard. There should always be eight types of (not eight total) power facility cards; if there are fewer than eight, a new one is drawn immediately from the pile. This is repeated until all the players have bought the cards they want to purchase in the field.
Appendix A.2.3. Phase 3: Event
Event cards are drawn from the pile to generate events. Two, three, and four event cards are drawn from the pile at the first, second, and third rounds, respectively. Unless otherwise stated, the impact extends to all players.
Appendix A.2.4. Phase 4: Purchasing Resources
Players purchase resources in the field or sell possessed resources to the market (field) in the order shown on the mainboard. Only one die can be purchased at a time, but selling more than one die is permitted. Players may purchase any resources regardless of the power generation facility they own, but the maximum number of resources, namely dice, they can possess depends on their development level, which can be increased with an investment card.
Appendix A.2.5. Phase 5: Power Generation
Players generate electricity to meet the required power and GHG emission limits by combining the power generation facility cards and the resources that they own. Power generation facility cards are available multiple times, while resources are consumables. Coal-, oil-, and gas-fired power plants emit 40, 30, and 20 GHG, respectively, per TWh of electricity generated. Thus, if the GHG limit is 600, for example, coal-fired power plants alone can generate only 15 TWh. After all players finish the power generation, the player marks are arranged in ascending order of power generation in the “order of purchase” on the mainboard. This is the end of the third round, which signals that the scores should be calculated.
Appendix A.2.6. Phase 6: Revenue
Each player earns (150 billion × development level) JPY. Those whose power generation at Phase 5 is less than the required power must pay JPY 5 billion to the bank for each 0.1 TWh shortfall after receiving income, while those whose power generation exceeds the power required by 3 TWh or more have to pay JPY 100 billion to the bank.
Appendix A.2.7. Phase 7: GHG Reduction
Players whose purchase order is not first will reduce their GHG limit by 50 or pay purchase order × JPY 20 billion to the bank. A player in the first purchase order can choose not to reduce the GHG limit or reduce the GHG limit by 50 and receive the whole amount of money that the other players paid.
Appendix A.2.8. Phase 8: Resource Market Update
One die for each resource is rolled to change the resource price; the marks on the fuels price table are moved downwards according to the dice roll. Coal and uranium are then replenished until there are six, and oil and gas are replenished by two (but the maximum number of dice in the field per resource type is six). Then, all the dice in the field are rolled again.
Appendix A.2.9. Phase 9: Development
Players whose power generation in Phase 5 satisfied the power requirement increase their development levels from +1 to +3 from the current level (+0 is not allowed). The development levels of players who failed to satisfy the requirement will be reduced to the level at which the amount of power generated in this round can meet the required power. In addition, players can increase their development level by another +1 for every JPY 100 billion they pay (no upper limit).