The electricity sector decarbonized through coal retirements and renewable deployment. Residential direct emissions — overwhelmingly natural gas heating — have barely budged. This is the sector electrification targets, and the economics explain why it hasn't moved.
GHG emission change by sector, 2005–2021
-28%
Electricity sector reduction — coal retirements and 7,319 MW approved solar. The power sector is the success story.
Residential buildings context
Residential direct emissions, 2021
9.8 MMTCO2e
Down only 0.4 from 10.2 in 2005. Primarily natural gas space and water heating.
Reduction since 2005
-4%
Smallest decline of any sector that fell. 16 years moved the needle less than 1 percentage point per year.
Commercial buildings (direct)
+7%
Commercial emissions actually rose — 6.3 to 6.7 MMTCO2e. More buildings, more gas.
Focus on Energy lifecycle gas savings
297M therms
2024 savings alone. High performance — but insufficient to bend the sector curve.
HP operating cost at flat rate
1.5–2.1x gas
At current tariff rates, electric heat pump heating costs more than gas. This is why the sector hasn't moved.
The electricity sector dropped 28% because utilities retired coal and built renewables — decisions made at the corporate and regulatory level. Residential emissions dropped 4% because individual households didn't switch from gas to electric — a decision driven by personal economics.
Current flat rates make HP heating 1.5–2.1x gas. HOMES/HEAR address upfront cost but not ongoing operating cost. Until rate design closes the gap, households will continue choosing gas — and this bar will continue not moving.
Sources: Primary sector emissions from "WI GHG Emissions Inventory (1990–2021)," WI DNR, in CEP 2025, Table 1: Electricity -28% (58.6→42.1), Residential -4% (10.2→9.8), Commercial +7% (6.3→6.7), Industrial -25% (15.1→11.4), Transportation -2% (42.7→41.7), Agriculture +20% (17.1→20.5), Waste -5% (5.2→5.0). Sub-sector breakdowns (imported electricity, natural gas & oil systems, industrial process) derived from WI DNR GHG Inventory detailed tables. Focus on Energy 297M therms — CEP 2025, p.20. Solar approved (7,319 MW) — CEP 2025, p.17. HP cost ratio from WPSC Rg-1 ($0.14802) and WE Rg1 ($0.19342), COP 3.0, vs gas ~$9/MMBtu.