Thursday, September 29, 2016

U.S. biofuel consumption chart through 2015

Just to provide an updated picture of the rise in U.S. biofuel consumption, here's a chart based on the latest annual data from EIA's Monthly Energy Review (MER). 

As of calendar year 2015, U.S. ethanol consumption was 13.9 billion gallons per year, up from 1.7 billion gallons in 2000. In 2000, biodiesel consumption was below the level of significance for EIA reporting (i.e., statistically zero relative to overall U.S. motor fuel use). Biodiesel consumption reached 1.5 billion gallons in 2015, and so total biofuel consumption amounted to 15.4 billion gallons that year.

For context, U.S. motor gasoline consumption was 140 billion gallons and distillate fuel oil (which is mostly but not all highway diesel) was 61 billion gallons last year.

In terms of carbon, biofuels accounted for 4.7% of total direct CO2 emissions from the U.S. transportation sector in 2015.

A short URL for embedding this chart is: If you use it, please credit this blog. The source data can be downloaded as Tables 10.3 (for ethanol) and 10.4 (for biodiesel) from the Renewable Energy section of EIA's MER webpage.

Saturday, September 17, 2016

Tailpipes top smokestacks as nation's largest CO2 emitters

Transportation, which runs almost entirely on petroleum fuels, and electricity generation, which had used mainly coal, have long been the largest sources of CO2 emissions in the United States. Although power plant smokestacks exceeded motor vehicle tailpipes and other mobile sources such as aircraft in terms of CO2 emissions for nearly forty years, this year brings a crossover of these two emission trends. The CO2 emitted by the transportation sector has been greater than that from the power sector for seven of the past eight months, and so 2016 is on track to see mobility overtake electricity as the country's biggest contribution to global warming.

The two sectors' emission levels were essentially tied in the late 1970s. Then the back-to-back insults of the 1973 Saudi-led oil embargo and the 1979 Iranian revolution triggered price and policy changes that that fostered a 68% increase in average new car and light truck on-road fuel economy by 1987. That efficiency gain curtailed transportation fuel demand and CO2 emissions for the next two decades. Meanwhile, electricity use continued to grow and until recently relied mainly on coal as its source of energy.

Since reaching a peak in 2007, electric sector emissions have fallen at an average annual rate of 2.8 percent through last year. Although the recession dampened power demand, the big story was the rejuvenation of domestic natural gas production due to fracking. Combined with progress in wind and solar power and ongoing energy efficiency gains, the result was a 20% drop in U.S. electric sector CO2 emissions over the past eight years, from 2.5 billion metric tons per year in 2007 to 2.0 billion tons per year in 2015.

CO2 emissions from transportation also fell during the recession. Moreover, auto efficiency was by then rising again due to higher pump prices and stronger Corporate Average Fuel Economy (CAFE) standards soon amplified by new motor vehicle greenhouse gas (GHG) emissions standards. However, the decline in transportation sector CO2 emissions was short lived. Starting in 2012, economic recovery and a moderation of motor fuel prices have turned the sector's CO2 emissions upward. The rate at which carbon is emitted from mobile sources rose at an average rate of 1.8 percent per year over the past four years. Calendar year 2015 saw transportation and electricity generation in a statistical tie as sources of CO2.  

Monthly data from the Energy Information Administration (EIA) indicate that, averaged over the year, transportation will top power production in 2016. The adjoining chart shows the most recent trends as a 12-month running average, placing the crossover in February. 
A closer look at the data is provided in the Technical Brief cited below. Electricity demand is highly seasonal, with a pronounced summer air conditioning peak and a smaller peak during the winter heating season. EIA reports monthly energy data with a three-month lag, so we don't yet know whether this summer's peak power production resulted in CO2 emissions levels greater than those from what is typically a much more modest peak in travel during the summer months. Nevertheless, the recent trends, as well as projections from EIA's Annual Energy Outlook, show that we've now entered a period where the transportation will be the nation's largest source of CO2 emissions.

That will be certainly be the case as the Clean Power Plan (CPP) plays out. Prior to the CPP, motor vehicle GHG emissions regulations were the country's most effective carbon control measure. These standards, which limit tailpipe emissions from personal vehicles as well as freight trucks, will keep transportation emissions from growing rapidly. But they won't put the sector on a steadily declining trend in the way the CPP will progressively trim GHG emissions from power plants. 

This development highlights a question with which transportation energy researchers been grappling. Beyond motor vehicle standards -- the only policy demonstrably effective to date for curtailing transportation CO2 emissions at a national scale -- what else should be done to mitigate the sector's contribution to climate disruption? 

For more details, see:
DeCicco, J.M. 2016. Transportation is Overtaking Electricity Generation as the Largest Source of U.S. CO2 Emissions. Technical Brief. Ann Arbor: University of Michigan Energy Institute. 

Thanks to Sam Ori for alerting us to these trends in a Vox article by Brad Plummer. 

Friday, June 3, 2016

Will car companies do better than coal companies in embracing the climate challenge?

Today in Slate, Daniel Gross published a thought-provoking piece entitled "Could Coal Have Survived by Going Green?" It highlights how the industry itself contributed to its own demise not only by fighting environmental policies but also by failing to invest in ways to utilize coal much more cleanly.

Coal fueled the industrial revolution and even in this post-industrial era it still provides a bedrock source of energy for much of the world. Although now overtaken by natural gas for generating electricity in the United States, coal remains second only to oil as the world's largest source of commercial energy. Its low resource cost could give it a role even in an increasingly climate-constrained future. But for that to happen, the industry's leaders would have had to embrace carbon mitigation as a worthy, investment-stimulating challenge instead of spending down their dwindling political capital to fight the inevitable.

One can see some parallels here to the recent near-death crisis of U.S. domestic automakers. Although General Motors, Ford and Chrysler had often talked a green line and showed off a few token green-branded products, for many years their major investment and lobbying strategies emphasized evading energy and climate policies instead of embracing them.

Monday, May 23, 2016

Latest tweak to U.S. biofuel mandate is politically correct and ecologically cruel

EPA's new Renewable Fuel Standard (RFS) proposal modestly increases the amount of biofuel that America's cars and trucks have to consume next year but still keeps the total renewable fuel mandate below the Congressionally scripted target.

In the plan released on May 18, ordinary corn ethanol gets a 300 million gallon boost, biodiesel is bumped up by 100 million gallons and other so-called advanced biofuels see a 200 million gallon increase compared to last year's regulation. Nevertheless, the proposed 18.8 billion gallon total remains significantly lower than the 24 billion gallon goal for renewable fuel in 2017 that Congress wrote into law back in 2007.

EPA's approach reflects a compromise worked out last year after several tortuous years of regulatory delay. This "politically correct" strategy has the agency taking a middle road that balances the money-making interests of the biofuel industry and the corn and soybean lobbies against the engineering and economic realities that render ethanol and biodiesel such inferior motor fuels. Reactions to the proposal were predictable. The renewable fuel lobby and its allies complain "that's not enough" while the oil industry and other critics say "that's too much" biofuel.

Wednesday, March 16, 2016

House Oversight Testimony on the RFS

I wish to thank the Chairs, Ranking Members and other members of the committee and subcommittees for inviting me to today’s hearing.

My name is John DeCicco and I am a research professor at the University of Michigan Energy Institute. My main focus is transportation fuel use and its environmental impact. I hold a doctorate in engineering from Princeton University and have worked on America's energy challenges for nearly 40 years, including 21 years at environmental organizations before returning to academia in 2009.

My recent research has included scientifically rigorous evaluations of the Renewable Fuel Standard (RFS) and other policies that promote biofuels such as ethanol and biodiesel. RFS proponents claim that the policy reduces CO2 emissions. I have found that it does not. In fact, from its inception, the RFS has increased rather than decreased the amount of CO2 entering the atmosphere compared to petroleum fuels such as gasoline.

Thursday, February 4, 2016

Fuel Economy Matters

Pump prices are down and given the outlook of a weak global economy, a strong dollar and a lingering oil glut, they could drop even more as the year goes on. The U.S. average retail gasoline price fell below $2.00 per gallon in January and as of last week it averaged $1.93 per gallon. For over a year now, it's been significantly lower than the roughly $3.50 per gallon average of the previous few years, let alone the brief spike to over $4.00 per gallon in summer 2008. 

Consumers respond to gasoline prices and so it's no surprise that new vehicle sales are at a record high while the vehicle mix has shifted away from compact segments and back to trucks, larger SUVs and more luxurious cars. The amount of driving is back up as well. 

The fuel economy of the vehicle fleet doesn't totally backslide even when the price of fuel does. Most efficiency gains are due to improved technology; once such engineering refinements are made they don't get undone. Corporate Average Fuel Economy (CAFE) standards prop fuel economy up even when consumer interest fades, and that policy is now reinforced with greenhouse gas (GHG) emissions standards that limit the amount of carbon dioxide (CO2) and other GHGs exhausted from tailpipes. 

Average new car and light truck fuel economy (right-hand axis) 
compared to nominal and inflation-adjusted gasoline prices. 
The adjoining graph compares the average fuel economy of new cars and light trucks to the price of gasoline since 1970, shown as both nominal "dollars of the day" and inflated to 2015 ("real") dollars. It's clear how fuel economy ratchets up as fuel prices rise. We can also see the slow backsliding that happened from the late 1980s until a decade ago. Although fuel economy has been climbing since 2005, we may be in for a serious tug-of-war between the need to keep fuel economy heading up and weakened consumer interest due to lower gasoline prices. 

Friday, December 11, 2015

Questions and responses on RFS testimony

House Science Committee Hearing on the RFS, November 3, 2015
(photo credit: Michael A. Waring) 
Following the recent hearing on the Renewable Fuel Standard (RFS) held by the House Science Committee, the subcommittee chairs asked me to respond to some questions for the record, following up on my testimony at the hearing. Here are the questions and an abbreviated version of the answers, summarizing my full written response

In his testimony, Mr. Coleman referenced cellulosic ethanol that is "129 times better than gasoline on carbon emissions." Based on your research, is this a reasonable claim?

No, that is not a reasonable claim. Such assertions are based on paper studies of hypothetical ethanol production methods. There is indeed a literature on the subject that applies lifecycle analysis (LCA) to proposed cellulosic ethanol production methods and projects that the resulting systems would not only fully offset tailpipe CO2 emissions but also offset other CO2 emissions such as those from fossil-based electricity generation.

However, as pointed out in my testimony (and in papers explained elsewhere on this blog), the LCA methods used to justify such claims are scientifically incorrect. Moreover, the cellulosic processing methods involved remain speculative as far as any meaningful commercial-scale operation is concerned. In short, claims of biofuels that achieve a more than 100% reduction in carbon emissions are rooted in flawed analysis of fantasy fuels. 

Wednesday, December 9, 2015

Think Progress and Out-of-Touch 'Persuasion'

There's no doubt that shifting political opinion toward effective climate action is going to take a lot of persuasion, especially of individuals and policymakers who don't already believe in the urgent need to drastically limit greenhouse gas emissions, or at least tend to rate the environment high on their list of concerns. 

But advocates trapped in the mental boxes of green-group group-think -- and that includes the dear former California governator, Republican though he may be -- are unlikely to change the minds of those in the most need of persuasion by approaching the issue as touted in this recent piece, "Did The Governator Just Come Up With A Republican-Proof Argument On Climate Change?" on Think Progress. 

The question that Mr. Schwarzenegger posed on Facebook was along the lines of "What room with a sealed door would you be rather trapped in, one with a gasoline car running at full throttle or one with an electric car running flat out?" (on treadmills, we presume).

Tuesday, November 3, 2015

Testimony on the RFS

Here's my statement at today's House hearing on the RFS; see links at the end to access the written testimony and related videos. 

My research shows that the Renewable Fuel Standard, or RFS, has been harmful to the environment from its inception. Now, ten years after the 2005 Energy Policy Act, the program has resulted in higher CO2 emissions than would have occurred otherwise. It also harms the environment in other ways. Sadly, the adverse impacts of the RFS have grown worse since it was expanded by Energy Independence and Security Act (EISA) of 2007.

The notion that renewable fuels readily reduce CO2 is based on a scientifically incorrect understanding of carbon neutrality. Only under certain conditions does substituting a biofuel for a fossil fuel neutralize the CO2 leaving the tailpipe. For that to occur, harvesting the feedstock must significantly increase how rapidly cropland absorbs CO2 from the atmosphere on a net basis. That condition is not met for the corn ethanol mandated by the RFS. It might be satisfied for cellulosic feedstocks, but once properly evaluated, the gains may not be as great as advocates assume.