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Example 7.8 (Where gas beats coal)

With gas at $35\,\mathrm{EUR}/\mathrm{MWh}$ of fuel, coal at $12\,$, efficiencies of 55% and 40%, and emission factors of 0.202 and 0.341 tonnes per MWh of fuel (illustrative round numbers), a MWh of electricity emits 0.367 t from gas and 0.853 t from coal, and the switching price is $69.32\,\mathrm{EUR}/\mathrm{t}$. At $70\,\mathrm{EUR}/\mathrm{t}$ and power at $100\,\mathrm{EUR}/\mathrm{MWh}$ the clean spark spread is $10.65\,$ and the clean dark spread $10.32\,\mathrm{EUR}/\mathrm{MWh}$: gas is just ahead.