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Coal power plant creates merit order for 8MWh@$230
Gas plant creates merit order for 8MWh@$240
Result: Solar power plant will produce 4MWh, coal power plant will produce 6 MWh. Tick algorithm will favor offer from Solar power plant because its cheaper. Spot price will by $230 because merit order from coal power plant was at least partially used so maximum price from used orders is $230.
Solar plant owner will receive 4 * 230 = $920
Coal plant owner will receive 6 * 230 = $1380 and also damage for causing overload (2MWh)
Gas plant will receive only damage for causing overload (8MWh)
City will grow in future ticks because demand was satisfied.