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Coal is 820 to 1050 kg of CO2e per Megawatt Hour
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Natural gas is 480 kg CO2e per Megawatt Hour
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Nuclear is 20 to 50 kg CO2e per megawatt-hour
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Wind is 25 grams of CO2 per Megawatt Hour.
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Solar is 20-50 grams of CO2 per Megawatt Hour.
(Numbers should not be considered accurate but relative scale is representative)
The biggest issue here is that without a significant increase in battery capacity a stable renewable grid is impossible without Natural Gas powered generation.