Tables 15 and 16 show net change in annual GHG emissions due to an incremental increase in each technology above current levels to reach the scenario target. The incremental increase varies across scenarios, as some technologies are already utilized to a greater degree and others have limited development potential. While renewable energy options do release greenhouse gases, in general they will reduce overall emissions by reducing fossil energy use. Table 15 assumes that renewable electricity first replaces coal, then oil, then nuclear (for intermittent sources, this is an optimistic assumption, as wind energy modeling predicts that natural gas will be the primary electricity resource displaced 41). Table 16 assumes that renewable heat/process energy replaces first oil, then propane; and that renewable transportation energy replaces gas and diesel at their current 80/20 ratio. Table 15: GHG Emissions Reductions for Renewable Electricity Scenarios Inland Wind 25%
Offshore Wind 25%
Woody Biomass Electricity 21%
Regional Hydro 23%
Canadian Hydro 25%
Distributed Solar 25%
Demand Reduction for Electricity 25%
Incremental increase in energy 12,692 14,048 8,418 4,033 8,052 14,048 14,048 output from this source (GWh) Annualized emissions from construction and 215,764 182,625 496,670 72,598 161,041 772,642 -operation (metric tons) Annualized emissions from 93,139 30,831 190 289 20,059 --transmission construction (metric tons) Land clearing or wood combustion 358,649 91,520 12,384,825 8,019 767,764 --emissions (metric tons) Emissions from natural gas 703,645 637,220 ---283,208 -balancing (metric tons) Reduced emissions from replaced 3,486,334 3,512,099 3,405,130 3,321,817 3,398,175 3,512,099 3,512,099 sources (metric tons)* Annual net -2,839,166 emissions reduction -2,115,137 -2,569,904 to -3,240,912 -2,449,311 -2,456,249 -3,512,099 (metric tons) +9,476,554# *Assumes that renewables first replace coal, then oil, then nuclear. Wind or solar alone cannot replace baseload coal or oil sources, but combining intermittent sources with natural gas reserves allows them to function similarly to today’s baseload sources. #Range for wood is without or with wood combustion emissions.
Cumulative Landscape Impacts of Renewable Energy Alternatives for Northern New England
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