Power futures on Tokyo Commodity Exchange, which the exchange calls Electricity Futures in English, come in three area products, on the Tokyo, Kansai, and Chubu area prices of the Japan Electric Power Exchange. Each has a baseload product, covering all 24 hours of the day, and a peakload product, covering weekdays from 8:00 to 20:00. For monthly contracts, which cover one month of electricity, the baseload trading unit is "calendar days in the month × 24 hours × 100 kWh," so one contract for a 30-day month is 72,000 kWh.
Consider a hypothetical example in which one contract is bought at 10 yen per kWh and the final settlement price is 12 yen. The buyer receives (12 − 10) × 72,000 kWh = 144,000 yen. If the final settlement price is 8 yen, the same calculation means the buyer pays 144,000 yen. The seller's amounts are the same with the opposite sign.