Category Archives: green source

Electric Vehicles, Coal & Dirty Electricity

Coal in Stocking

Since it is the Holiday Season, and some traditions continue, such as busting PEVs because they allegedly use dirty electricity and can’t then be zero emission, I include this brief op-ed from last week for your reading pleasure.  The final take away is simple- where you live and how your local utilities get their electricity do play a role in how clean your PEV runs and since most states increasingly support alternative forms of renewable energy, your PEV will likely continue to get cleaner.  So enjoy the season and stop feeling guilty!

Tuesday’s Portland Press Herald Article by Seth Borenstein, titled, “For electric cars, it’s not simple to be green,” offers outdated and misguided commentary on the issue of “dirty” electricity and whether electric vehicles are more of a problem than a solution when it comes to transportation-based emissions.  As a study released by the Union of Concerned Scientists in 2012, “State of Charge; Electric Vehicles Global Warming Emissions and Fuel-cost Savings across the United States” concluded, EVs are vastly superior in their emission profiles over most regions of the US.  It boils down to where the electricity comes from.  If you live in the Wyoming where coal is used for base load generation, your EV does contribute to GHG emissions on a par with a combustion engine.  That is one reason why coal-fired power plants are no longer viable for electricity generation and are being moth-balled.  Conversely, if you live in Maine, with an increasingly healthy mix of renewable energy generation sources, including wind, tidal, hydro, solar and biomass and the cleanest grid in New England, operating your electric vehicle is much less carbon intense than your neighbor’s gas-powered car.  The good news is most states, like Maine, have a renewable portfolio standard that has resulted in ongoing efforts to clean up their electricity generation, so an EV actually drives cleaner the longer you own it!  That is not true of your gasoline vehicle.  Mr. Borenstein chooses to highlight the coal connection rather than the clean connection.  I leave you with the final sentence of the PNAS study quoted by Mr. Borenstein, which reads, “Consideration of potential climate change impacts alongside the human health outcomes described here further reinforces the environmental preferability of EVs powered by low-emitting electricity relative to gasoline vehicles.” (Emphasis added).

Maine, and all the New England states, should be proud of their efforts to promote clean electricity and their EV-owners can drive with clear consciences.

Follow this link to go to my actual op-ed.

Zero Means Zero


There has been some press lately calling into question the actual carbon footprint of operating a battery electric vehicle (BEV).  There is logic behind this.  Utilities quite commonly generate carbon emissions from their portfolio of generation sources, whether natural gas driven turbines or coal plants.  They (the investor owned utilities like PGE or PacifiCorps) are obligated as regulated monopolies to provide power on demand to our society, no matter that demand’s daily and seasonal peaks and troughs.  As a result they have devised an ingenious system that includes baseload power generation sources (those which can economically and reliably provide most of our power needs, day in, day out) and peaking plants to cover exceptional power needs.  The source of this baseload power is highly dependent on the region served.  The Southeast and Northeast have had little historic choice but to rely on fossil fuels, such as coal and natural gas, to feed their demand.  They lack cheap, natural resources.  The Northwest has the happy fate of enjoying a deep bench of low or zero emission generation sources starting with the Columbia River Basin Hydro-system (which generates almost 50% of the region’s power depending on snowpack) and extending out into the Gorge through Sherman and Morrow Counties where currently 2300 mWh of wind generation (valued at $4.5b) has been installed.

So how do you respond when someone says an EV’s electrical use is not “clean”?

First, zero emission vehicles are simply defined as emitting no combustion byproducts from their tailpipe.  At this level, and it is a reasonable level, all BEVs qualify as zero emission.  In congested, urban settings, preventing the introduction of additional emissions has tangible environmental and health benefits. Of course, the argument then turns to the generation source of electricity, often located far away from the urban centers who benefit most from the generation,  and whether that contributes CO2 emission and merely displaces its impact to rural settings. An analysis requires each EV owner to be familiar with the source of his/her region’s baseload electrical generation (which you should be able to get directly from your electricity provider.)

“Even in the worst-case scenario where 100 percent of that generation is from coal, there is still a net positive emissions trade-off,” Glenn Stancil  of NRG Energy VP said. A 2007 study found that a plug-in hybrid electric vehicle charged with electricity from a coal plant would result in 25 percent less carbon dioxide emissions than a conventional gasoline vehicle, he said. The study was conducted by Electrification Coalition, a trade group of which NRG is a member.

A study by Jan Kreider, founding director of the University of Colorado‘sJoint Center for Energy Management, found similar results.

It bears noting that EVs are much more efficient in converting energy to movement compared to their gas counterparts, which means they still create less carbon emissions per mile.  In that sense, even if we kept coal and natural gas electric generating plants, and added to them, as a country we would still experience a net decline in carbon emissions if our light-duty/passenger fleet converted over entirely to BEVs.

We can do better.  In the Pacific Northwest we have the unique ability to charge our BEVs with truly clean electric power. Portland General Electric sponsors its Green Source Program, which adds 1.2 cents per kWh on my monthly bill.  For this, I receive a 100% renewable energy mix ranging from low-impact hydro, to wind to geothermal.

Zero can truly mean zero.