Monday, December 24, 2012

Time for realism on renewable fuels

This month, the Environmental Protection Agency upheld its requirement for blending ethanol into gasoline. Though not unexpected given the strength of renewable fuel interests, this decision ignored the pleas of 10 governors, almost 200 members of Congress and many Michigan businesses. With drought destroying much of America's corn crop this summer and Thanksgiving dinners costing significantly more since 2005, the downsides of renewable fuels became all too clear. Responsibility now falls to Congress to roll back the unrealistic renewable fuel goals set in the Energy Independence and Security Act (EISA) of 2007.

To understand how we got to this unhappy place, a bit of history is needed. Renewable fuels such as ethanol and biodiesel have long been hailed as alternatives to America's reliance on petroleum. The fuels bolster crop farmers' incomes and claim to protect the planet by recycling carbon from the air. As prices at the pump climbed over the last decade, biofuel proponents rallied support for a mandate to replace petroleum with home-grown biofuels.

Wednesday, September 12, 2012

Shell Canada's call for carbon management

The Globe & Mail reports that the president of Royal Dutch Shell Canadian division said that "carbon management" must be part of an approach to balance protecting the environment with meeting the need for oil and gas.

Shell is one of several companies exploiting Canada's tar sands, where oil extraction typically releases significantly more CO2 than crude production from conventional oil fields. Oil and gas companies have been working on ways to reduce the environmental impact, particular excess CO2 emissions that has come with tapping the extensive petroleum reserves associated with the tar sands resource. One of the options for doing so is carbon capture and storage (CCS).

In a project known as "Quest" partly supported by the Canadian government, Shell is putting together a system to capture CO2 from an upgrader near Edmonton, Alberta. The upgrader processes the heavy bitumen extracted from the nearby Athabasca tar sands to an oil that can be refined like conventional crude oils. The Quest project is slated to start operating in late 2015 and aim to capture one million tonnes a year of CO2 that would otherwise be emitted by the upgrader. The captured CO2 will be piped to a location about 80 km away for injection and storage in a porous sand formation that rests about 2 km underground beneath layers of impermeable rock.

Shell's Canadian division president, Lorraine Mitchelmore, pointed out that such CCS technology will not be widely adopted unless there is a price on carbon. In discussing this policy need, she implicitly clarified the figurative nature of the phrase, "price on carbon", noting that it could be achieved not only by imposing a carbon tax, but also through a cap-and-trade system or CO2 emissions regulations.

Monday, September 3, 2012

Thinking about a regional liquid fuels carbon study

One way we might better understand the opportunities to counterbalance the carbon in liquid fuels is to assess the immediate opportunities in a given region. Being based in Michigan, a midwest regional scope makes sense for practical reasons. Such a scope is of particular research interest for several other reasons as well:
  • Michigan, and the industrial midwest more generally, is home to the U.S. auto industry as well as a major global center of automotive research and manufacturing. The auto industry can potentially benefit from the identification of cost-effective options for counterbalancing the CO2 emissions from the use of their products. 
  • The midwest is the heart of the U.S. biofuel industry, where most corn ethanol production is located, and is a major agricultural region with extensive rural land now used for many purposes (including suburbanization) but which could also have a significant potential for reforestation or other forms of terrestrial carbon uptake and storage. 
  • The midwest has been struggling economically, as its traditional industries have both increased productivity (reducing the need for labor) and been adversely affected by outsourcing many aspects of production. New opportunities for value creating tied to the land itself could provide robust economic opportunities for the future. 
  • Much of the region has dispersed settlement patterns and so is not particularly suitable for either extensive mass transit or vehicle electrification based on available and near-term technological capabilities. Therefore, its transportation systems will remain almost exclusively dependent on liquid fuels for the foreseeable future. 
The region is already experiencing climatic risks of the sort expected to worsen as global warming progresses. Most of the region's political leaders have opposed strong policies for GHG mitigation (opposition that is by and large bipartisan, though it may be expressed differently by members of different parties). However, this policy challenge may be related to the fact that many proposed solutions are seen as having an adverse economic impact on the region's interests, given its historical heavy industry and agricultural base and dependence on coal for power generation. Identifying new opportunities for carbon mitigation that work better with the region's resources and economic base may be more attractive politically than what has been previously proposed. 

Sunday, August 26, 2012

Generalizing what biofuels do

Many people have thought of biofuel as the ideal way to replace petroleum fuels. Biofuels can be liquids, and in fact, "liquid fuel made from biomass" is the most common meaning of the term. Because the focus here is on liquid carbon, liquid forms are the biofuels of interest. Examples include ethanol and biodiesel.

Basic chemistry tells us that the amount of CO2 released when burning liquid fuels is essentially the same for a given amount of energy provided. However, the common view is that biofuels are inherently carbon neutral. That's because the CO2 released when the biofuel is burned is offset by the CO2 that was taken up from the atmosphere when the fuel's biomass feedstock was grown. Combine this fact with the fact that biofuels can be produced from home-grown biomass, and it's easy to see why biofuels have such enormous appeal as replacements for oil.

The LCA script

Lifecycle analysis (LCA) is a very popular form of environmental assessment. A good number of academics and others assert that it is the ideal way to examine greenhouse gas emissions impacts and so advocate LCA as a way to compute "carbon footprints."

This view has come to dominate energy policy discussions of ways to reduce GHG emissions from transportation fuels. In particular, nearly everyone involved in the issue says that biofuels should be evaluated according to their full lifecycle impacts. As the major UNEP report on Assessing Biofuels puts it, "Environmental and social impacts need to be assessed throughout the entire life-cycle."

However, biofuel LCA has become ever more complex and has resulted in models that are no longer even close to being scientifically verifiable. Therefore, no amount of new data that one puts into a lifecycle study can put an end to the disputes over LCA-based estimates of the net GHG impact of biofuels. This argument is made in the paper "Biofuels and Carbon Management" Climatic Change (2012), which then proposes a different approach to analysis.

Saturday, August 25, 2012

Liquid fuels and carbon dioxide

A most troubling aspect of the global climate problem is the carbon dioxide (CO2) emitted by petroleum consumption. Oil is still the world's largest source of energy, though it now runs second to coal as a direct source of anthropogenic CO2 emissions. Oil is a liquid and is by far the main feedstock for liquid fuels, i.e., hydrocarbon energy carriers such as gasoline, diesel, jet fuel, bunker oil and so on.

Carbon dioxide
Combustion of any liquid hydrocarbon fuel directly releases an amount of CO2 that varies only a little depending on the fuel. This is true for most carbon based liquids, not just strictly hydrocarbons. For example, burning ethanol directly releases only about 2% less CO2 than gasoline for a given amount of energy provided.

Therefore, in terms of direct emissions, changing the form of the liquid fuel, e.g., from gasoline to ethanol or from diesel to biodiesel, makes no appreciable difference in the amount of CO2 released to the atmosphere. 

Therefore, as long as society burns liquid fuels -- and we now consume enough of them to make oil the world's number one source of commercial energy -- we have what can be called a "liquid carbon" problem. I'll leave to others the tasks of thinking about how to replace liquid fuels, for example, with electric cars or hydrogen-powered vehicles, using energy carriers that don't contain carbon atoms. Meanwhile, society has a huge liquid carbon problem to solve. 

Monday, June 4, 2012

An unheeded warning on ethanol

As concerns about the adverse impacts of expanding biofuel use continue to mount, I can't help but note that a number of policy analysts raised red flags about the issue a decade ago, when proposals to mandate biofuel use began to get legs in Washington. Such was the case for a short position statement opposing an ethanol mandate that I co-wrote while on staff at the Environmental Defense Fund (EDF).

The 9/11 attacks in 2001 shocked U.S. public sentiment in many ways, including a re-awakened concern about energy security and the risks of dependence on foreign oil, as many put it. Policymakers suddenly became much more willing to seriously back petroleum alternatives. Biofuels had long enjoyed a basic level of support, including subsidies established following the 1970's oil crises. Ethanol advocates now saw an opportunity to boost biofuel production in a political climate that made policymakers from both parties happy to intervene in the market as a way to show the public that they were taking action on energy security.

Bills to mandate ethanol in gasoline were introduced early in 2002. The policy immediately found support, especially in the Senate where heartland votes easily overcame the skepticism of members from the left and right coasts.

A number of environmental organizations viewed biofuels as a crucial renewable alternative to petroleum-based gasoline. Although the net benefits of corn ethanol were always questioned, some green campaigners thought it had at least modest benefits. Just as importantly, they believed that mandating ethanol would build a market that would eventually shift away from corn to hoped-for cellulosic feedstocks that were considered much more beneficial.

Along with fellow EDF staffer Tim Searchinger, I was then quite skeptical of ethanol. The position statement we wrote opposing the ethanol mandate argued that its greenhouse gas reduction benefits were small at best while the expansion of corn growing that it would induce would be harmful to wildlife and water quality.

Needless to say, cautious voices like ours were drowned out by the rising chorus of those who were promoting biofuels for one reason or another, from the understandable self-interest of corn growers and processors to energy security hawks and green advocates of renewable energy.

Although other policy disagreements prevented an energy bill from passing in 2002, the ethanol mandate was one of the most widely supported provisions. It was re-introduced in successive Congresses, passing as part of the 2005 Energy Policy Act and then being greatly expanded by the 2007 Energy Independence and Security Act (EISA).

In retrospect, our reasons for skepticism were even better founded than we knew at the time, and the ethanol mandate has turned out to be even more of an environmental disaster than we imagined.


Wednesday, March 14, 2012

Biofuels and climate: a simple but troubling view

If biofuels benefit the climate, it's not when they're burned; those CO2 emissions are the same as from the fossil fuels they replace. Any potential benefit is due to the CO2 uptake when plants are grown. Society should maximize that uptake and, once carbon is absorbed, do everything possible to keep it from getting back into the air. This almost certainly means not burning biofuels.