IEEE Power & Energy Magazine - July/August 2018 - 59

hampshire, and maine.) these decarbonization studies focus on achieving a 40% reduction in economy-wide ghg emissions
by 2030 (40 × 30), on the way to achieving an 80% reduction in ghgs by 2050 (80 × 50) relative to 1990 levels. although the
scope of ghg reduction goals in both regions is economy wide, the focus of this article is on impacts and implications for the
electricity sector, which will play a critical role in meeting these ghg targets.
in both regions, energy efficiency (ee) and renewable electricity (re) have been the focus of ghg reduction efforts to
date and already resulted in significant reductions relative to historic levels. however, ee and re on their own are insufficient to meet the 2030 and 2050 goals. significant reductions in transport and heat emissions will be necessary, with
electrification in transportation and fuel
switching for other end uses likely to play
a pivotal role.
there are low-carbon alternatives
to electrification, including biofuels and
hydrogen fuel produced from low-carbon
electricity. likewise, alternatives to re
include nuclear power or carbon capture
and sequestration. these alternative technologies are not the focus of this article
but have been investigated in other deep
decarbonization scenario analyses. in general, in the 2030 time frame, these alternatives appear to face either significant supply
constraints (in the case of biofuels) or cost challenges, in the case of hydrogen, nuclear, and carbon capture and sequestration.
against this backdrop, both studies focused on the power system implications of widespread electrification, with the goal
of understanding whether power system constraints could limit achievement of the 2030 ghg targets. We evaluate 2030
power system constraints using five metrics:
✔ Incremental electric energy requirements (gigawatthours): total electric energy requirements, and, in particular,
the growth attributable to new transportation and building loads, provide insights into the bulk energy system's ability
to meet total demand.
✔ Incremental peak demand requirements (gigawatts): Peak demand growth, a measure of the impact of new electrification loads on maximum capacity requirements for resource adequacy, also provides a useful proxy for potential
impacts on system reliability metrics. it is important to note that only average temperature conditions are tested. the
peak demand impacts of more extreme cold temperatures were not tested in this analysis and warrant further research.
✔ Curtailment (percent of RE): Curtailment occurs when electricity supply exceeds demand in any given hour, either
due to emergency conditions or because variable re (Vre) cannot be cost-effectively integrated onto the grid, and
renewable output must be reduced. quantifying the evolution of curtailment over time provides a useful proxy for
operational and economic challenges of grid integration.
✔ GHG emissions [metric tons carbon dioxide (CO 2 )]: to achieve ghg reduction goals, electrification must contribute to a net reduction in economy-wide ghg emissions, even if electrification causes electricity sector emissions to
increase on the margin.
✔ Electricity cost (average retail rate): electricity costs indicate whether the low-carbon energy system pathway is likely
to be sustainable from an electricity consumer perspective. Customers that adopt electric vehicles (eVs) and electrification in their buildings could see total energy bills that decrease, due to avoided fossil fuel costs. however, if electricity
rates increase significantly for nonadopting customers, this could cause a backlash against an electrification strategy.
each metric provides insights into how to manage the electricity sector transformation on the road to a lowcarbon future. While our studies used different research methods and models to test the impacts
of electrification, we reach similar conclusions based on these five metrics. the systemwide challenges of a highly electrified, highly renewable future appear
to be manageable in the 2030 time frame. if managed appropriately,
the electrification of transportation and building loads may

Electrification and Renewables
in California and the
Northeast United States

©istockphoto.com/JamesGdesiGn

july/august 2018

ieee power & energy magazine

http://www.istockphoto.com/JamesGdesiGn

Table of Contents for the Digital Edition of IEEE Power & Energy Magazine - July/August 2018