Category: Renewable energy

Zero Energy Buildings: They May Be Coming Sooner Than You Think

Buildings account for approximately 40 percent of the energy (electrical, thermal) used in the U.S. and Europe, and an increasing share of energy used in other parts of the world. Most of this energy today is fossil-fuel based. As a result, this energy use also accounts for a significant share of global emissions of carbon dioxide.

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Source: U.S. Department of Energy, Buildings Energy Data Book

These simple facts make it imperative that buildings, along with transportation fleets and power generation, be primary targets of reduced global energy and fossil fuel demand. This blog post discusses one approach in buildings that is gaining increasing visibility and viability, the introduction of net zero energy buildings and the retrofit of existing buildings to approach net zero energy operation. A net zero energy building (NZEB or ZEB) is most often defined as a building that, over the course of a year, uses as much energy as is produced by renewable energy sources on the building site. This is the definition I will focus on. Other ZEB definitions take into account source energy losses in generation and transmission, emissions (aka zero carbon buildings), total cost (cost of purchased energy is offset by income from sales of electricity generated on-site to the grid), and off-site ZEB’s where the offsetting renewable energy is delivered to the building from off-site generating facilities. Details on these other definitions can be found in the 2006 NREL report CP-550-39833 entitled “Zero Energy Buildings: A Critical Look at the Definition”.

The keys to achieving net zero energy buildings are straight forward in principle: first focus on reducing the building’s energy demand through energy efficiency, and then focus on meeting this energy demand, on an annual basis, with onsite renewable energy – e.g., use of localized solar and wind energy generation. This allows for a wide range of approaches due to the many options now available for improved energy efficiency in buildings and the rapidly growing use of solar photovoltaics on building roofs, covered parking areas, and nearby open areas. Most ZEB’s use the electrical grid for energy storage, but some are grid-independent and use on-site battery or other storage (e.g., heat and coolth).

A primary example of what can be done to achieve ZEB status is NREL’s operational RSF (Research Support Facility) at its campus in Golden, Colorado, shown below.

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It incorporates demand reduction features that are widely applicable to many other new buildings, and some that make sense for residential buildings and retrofits as well (cost issues are discussed below). These include:
– optimal building orientation and office layout, to maximize heat capture from the sun in winter, solar PV generation throughout the year, and use of natural daylight when available
– high performance electrical lighting
– continuous insulation precast wall panels with thermal mass
– windows that can be opened for natural ventilation
– radiant heating and cooling
– outdoor air preheating, using waste heat recovery, transpired solar collectors, and crawl space thermal storage
– aggressive control of plug loads from appliances and other building equipment
– advanced data center efficiency measures
– roof top and parking lot PV arrays

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U.S. ZEB research is supported by DOE’s Building America Program, a joint effort with NREL, Lawrence Berkeley National Laboratory, Oak Ridge National Laboratory, and several industry-based consortia – e.g., the National Institute of Building Sciences and the American Institute of Architects. Many other countries are exploring ZEB’s as well, including jointly through the International Energy Agency’s “Towards Net Zero Energy Solar Buildings” Implementing Agreement (Solar Heating and Cooling Program/Task 40). This IEA program has now documented and analyzed more than 300 net zero energy and energy-plus buildings worldwide (an energy-plus building generates more energy than it consumes).

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An interesting example of ZEB technology applied to a residential home is NREL’s Habitat for Humanity zero energy home (ZEH), a 1,280 square foot, 3-bedroom Denver area home built for low income occupants. NREL report TP-550-431888 details the design of the home and includes performance data from its first two years of operation (“The NREL/Habitat for Humanity Zero Energy Home: a Cold Climate Case Study for Affordable Zero Energy Homes”). The home exceeded its goal of zero net source energy and was a net energy producer for these two years (24% more in year one and 12% more in year two). The report concluded that “Efficient, affordable ZEH’s can be built with standard construction techniques and off-the-shelf equipment.”

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The legislative environment for ZEB’s is interesting as well. To quote from the Whole Building Design Guide of the National Institute of Building Sciences:
“Federal Net Zero Energy Building Goals
Executive Order 13514, signed in October 2009, requires all new Federal buildings that are entering the planning process in 2020 or thereafter be “designed to achieve zero-net-energy by 2030”. “In addition, the Executive Order requires at least 15% of existing buildings (over 5,000 gross square feet) meet the Guiding Principles for Federal Leadership in High Performance and Sustainable Buildings by 2015, with annual progress towards 100% conformance”.
Two milestones for NZEB have also been defined by the Department of Energy (DOE) for residential and commercial buildings. The priority is to create systems integration solutions that will enable:
Marketable Net Zero Energy Homes by the year 2020
Commercial Net Zero Energy Buildings at low incremental cost by the year 2025.
These objectives align with the Energy Independence and Security Act of 2007 (EISA), which calls for a 100% reduction in fossil-fuel energy use (relative to 2003 levels) for new Federal buildings and major renovations by 2030.”

A word about cost: ZEB’s cost more today to build than traditional office buildings and homes, but not much more (perhaps 20% for new construction). Of course, part of this extra cost is recovered via reduced energy bills. In the future, the zero energy building goal will become more practical as the costs of renewable energy technologies decrease (e.g., PV panel costs have decreased significantly in recent years) and the costs of traditional fossil fuels increase. The recent surge in availability of relatively low cost shale gas from fracking wells will slow this evolution but it will eventually occur. Additional research on cost-effective efficiency options is also required.

To sum up, the net zero energy building concept is receiving increasing global attention and should be a realistic, affordable option within a few decades, and perhaps sooner. ZEB’s offer many advantages, as listed by Wikipedia:
“- isolation for building owners from future energy price increases
– increased comfort due to more-uniform interior temperatures
– reduced total net monthly cost of living
– improved reliability – photovoltaic systems have 25-year warranties – seldom fail during weather problems
– extra cost is minimized for new construction compared to an afterthought retrofit
– higher resale value as potential owners demand more ZEBs than available supply
– the value of a ZEB building relative to similar conventional building should increase every time energy costs increase
– future legislative restrictions, and carbon emission taxes/penalties may force expensive retrofits to inefficient buildings”

ZEB’s also have their risk factors and disadvantages:

“- initial costs can be higher – effort required to understand, apply, and qualify for ZEB subsidies
– very few designers or builders today have the necessary skills or experience to build ZEBs
– possible declines in future utility company renewable energy costs may lessen the value of capital invested in energy efficiency
– new photovoltaic solar cells equipment technology price has been falling at roughly 17% per year – It will lessen the value of capital invested in a solar electric generating system. Current subsidies will be phased out as photovoltaic mass production lowers future price
– challenge to recover higher initial costs on resale of building – appraisers are uninformed – their models do not consider energy
– while the individual house may use an average of net zero energy over a year, it may demand energy at the time when peak demand for the grid occurs. In such a case, the capacity of the grid must still provide electricity to all loads. Therefore, a ZEB may not reduce the required power plant capacity.
– without an optimised thermal envelope the embodied energy, heating and cooling energy and resource usage is higher than needed. ZEB by definition do not mandate a minimum heating and cooling performance level thus allowing oversized renewable energy systems to fill the energy gap.
– solar energy capture using the house envelope only works in locations unobstructed from the South. The solar energy capture cannot be optimized in South (for northern hemisphere, or North for southern Hemisphere) facing shade or wooded surroundings.”

Finally, it is important to note that the energy consumption in an office building or home is not strictly a function of technology – it also reflects the behavior of the occupants. In one example two families on Martha’s Vineyard in Massachusetts lived in identical zero-energy-designed homes and one family used half as much electricity in a year as the other. In the latter case electricity for lighting and plug loads accounted for about half of total energy use. As energy consultant Andy Shapiro noted: “There are no zero-energy houses, only zero-energy families.”

Animal Wastes: An Energy Resource That Is Win-Win

I first became aware of the animal waste issue in 1995 when a lagoon of liquid pig wastes in Iowa overflowed its banks and contaminated a nearby waterway. It made the national news, including the Washington Post, and resulted in one of my DOE colleagues asking me if we had a program to generate fuels/energy from such wastes. This was a logical question as I then headed DOE’s renewable electricity programs and biomass issues were under my purview. I answered honestly, no, but immediately headed to the offices of my biomass program and directed that such a program be started. I designated one of the senior biomass staff to head it up, it started the next day, and the new program head, a Ph.D, was unofficially given the title “Dr. Poop”.

Not having such a program earlier was clearly an oversight on my part, and I began to educate myself on the realities of animal wastes and their possibilities for productive application. One step was tracking down people in the DOE national laboratory system that knew about such things, and I found an expert at Oak Ridge. He directed me to useful information, of which there was quite a bit, and helped me organize an all-day meeting at the University of Tennessee with animal waste experts that explored these issues in detail. It was illuminating to say the least, especially for this boy from the Bronx who didn’t see his first bull until he was 16 and his first pig until he was in graduate school. I’ve never been the same since.

A few facts and numbers will put the issue in context. The U.S. produces lots of livestock (cows, chickens, turkeys, etc.) and therefore lots of animal wastes. Until recently the U.S. was the leading global meat producer but is now #2 behind China (42 million metric tons/MMT vs. 83 MMT), with Brazil coming in third at 25 MMT. EPA, which plays an important role in animal waste management in the U.S., estimates that this waste is produced on 1.3 million farms across the nation. The numbers of animals raised each year in the U.S. is staggering – more than 9 billion chickens, 250 million turkeys, 100 million beef and dairy cattle, 65 million pigs, and other animals (sheep, goats, ..) that are raised as part of our food economy. The net result of all this is about one billion annual tons of animal wastes – about ten times the amount of municipal sewage – that have to be dealt with in a way that does not jeopardize human, fish, or ecosystem health.

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Why are animal wastes a threat? Agriculture, including livestock, is a major source of nitrates that pollute water supplies. Animal wastes also contain disease-causing pathogens such as E coli, Salmonella, and Cryptosporidium that can be many times more concentrated than in human waste. “More than 40 diseases can be transferred to humans through manure.” Antibiotics added to animal feed to project against infection and speed up llivestock growth (about 30 million pounds annually, or 80% of antibiotic use in the U.S.) gets into human foods and contributes to the evolution of anti-biotic resistant bacteria. In addition, wastes at pig farms emit hydrogen sulfide, a corrosive gas that if inhaled at high concentrations can lead to brain damage and death.

Can’t we just contain this stuff so it doesn’t get into our water supplies? The facts are that some waste lagoons are as big as several football fields and are prone to leaks and spills.

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To quote the Natural Resources Defense Council:
“In 1995 an eight-acre hog-waste lagoon in North Carolina iburst, spilling 25 million gallons of manure into the New River. The spill killed about 10 million fish and closed 364,000 acres of coastal wetlands to shellfishing.

In 2011, an Illinois hog farm spilled 200,000 gallons of manure into a creek, killing over 110,000 fish.

In 2012, a California dairy left over 50 manure covered cow carcasses rotting around its property and polluting nearby waters.

When Hurricane Floyd hit North Carolina in 1999, at least five manure lagoons burst and approximately 47 lagoons were completely flooded.

Runoff of chicken and hog waste from factory farms in Maryland and North Carolina is believed to have contributed to outbreaks of Pfiesteria piscicida, killing millions of fish and causing skin irritation, short-term memory loss and other cognitive problems in local people.

Nutrients in animal waste cause algal blooms, which use up oxygen in the water, contributing to a “dead zone” in the Gulf of Mexico where there’s not enough oxygen to support aquatic life. The dead zone fluctuates in size each year, extending a record 8,500 square miles during the summer of 2002 and stretching over 7,700 square miles during the summer of 2010.

Ammonia, a toxic form of nitrogen released in gas form during waste disposal, can be carried more than 300 miles through the air before being dumped back onto the ground or into the water, where it causes algal blooms and fish kills.”

Complicating all this is the reality of ‘intensification’, the fact that “..smaller family farms have been replaced by corporate operations hounding thousands of animals in assembly-line conditions.” For example, the number of pig farms in the U.S. in 2011 was one tenth the number in 1980 but the number of pigs sold was about the same. Ten companies today produce more than 90% of the nation’s poultry and 70% of U.S. beef cattle come from farms with at least 5,000 head of cattle.

This concentration of livestock growing in factory farms, called concentrated animal feeding operations (CAFOs) is driven by economic imperatives. It leads to a buildup of animal wastes in small land areas, which if properly stored and used, can be a valuable resource. If not properly managed the waste produced by CAFOs can pollute the environment, especially water sources. Waste is often pumped into open-air lagoons from which liquid manure is sprayed onto fields as fertilizer. The amount of waste applied often exceeds what the crops can absorb, leaving the rest to escape into the air or as runoff into surface waters.

There are many productive uses of manure, including fuel and energy production. These include recovery of undigested anti-biotics, recovery of solid materials for use in building materials, and production of dry plant and crop fertilizer that is the byproduct of biodigestion. It is this latter activity that offers a ubiquitous and large energy resource.

As reported by the Agriculture Extension Division of Colorado State University: “The demand for clean energy, coupled with concern for management of livestock wastes, has revived an interest in generating methane from livestock manures. The most widely accepted technology currently available for converting organic wastes present in livestock manure is anaerobic digestion (AD). AD is a biological process by which microorganisms convert organic material into biogas, containing methane and carbon dioxide. Biogas produced by this process can be utilized to generate electricity or can be cleaned up and supplied to natural gas lines. Collection and utilization of methane generated from livestock manure offers the potential to reduce global emissions of methane (a greenhouse gas), reduce CO2 released from fossil fuels, diminish odor from agricultural facilities, and improve water quality. In many cases, anaerobic digestion either decreases on-farm energy costs or increases revenues from energy resale.” An interesting number is that, on average, “..a single dairy cow produces approximately 120 pounds of wet manure per day” which has an energy value of about 14,000 BTU. Thus, “It would take manure from approximately 50 cows to produce enough biogas for heating a typical home.”

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Proper management and use of animal wastes is clearly a ‘win-win’ if we can prevent water and air pollution and tap into a potentially large energy resource. For example, China is actively pursuing biodigestion of human and animal wastes, particularly in rural areas that lack grid connections, for producing biogas for lighting and cooking. The International Energy Agency’s CADDETT Reneable Energy Program (http://www.caddett-re.org) “..gathers information on full-scale commercial projects which are operating in the member countries..”. Its Renewable Energy Register, a database of demonstrated renewable energy projects, contains many biodigestion entities – e.g., ‘Poultry Litter as a Fuel for Electricity Production’, ‘Electricity and Heat from the Aanaerobic Digestion of Farm Wastes’, and ‘Centralized Manure Digestion Plant’. Information is readily available; what is now needed is widespread implementation.

Subsidies For Energy Technologies: Are They Fair?

Subsidies for energy technologies is a complicated and contentious issue and one that a few studies have tried to illuminate for the rest of us. For what I consider informative and balanced discussions I would refer you to
– ‘Reforming Fossil-Fuel Subsidies to Reduce Waste and Limit CO2 Emissions while Protecting the Poor’, Global Subsidies Initiative of the International Institute for Sustainable Development (iisd), September 2012
– Ken Silverstein’s October 23, 2013 piece in the e-journal energybiz entitled ‘Fossil Fuels and Green Energy Feed Mightily at the Public Trough’
– ‘Analysis & Projections: Direct Federal Financial Interventions and Subsidies in Energy in Fiscal Year 2010’, U.S. Energy Information Administration (EIA), August 1, 2011
– ‘Federal Financial Support for the Development and Production of Fuels and Energy Technologies’, Congressional Budget Office (CBO), March 2011.

There are many other useful sources of information as well. Of course vested interests on all sides of the energy debate have taken their shot at this topic. For example, the views of the fossil fuel industries can be found in the publications of the Institute for Energy Research (IER) and often in the pages of the Wall Street Journal. Supporters of subsidies for renewable energy technologies are active as well in expressing their views via statements by trade associations such as the American Wind Energy Association and the Solar Energy Industries Association. All in all, a difficult subject to get one’s objective hands around, but I will try (foolishly?) in this blog post. Admittedly a strong advocate for rapid progress toward a renewable energy future, I will try to be as balanced as I can in my discussion, as I truly want to better understand this subject and believe that informed public opinion is the long term prerequisite to a sustainable energy future. I will let you judge how successful I have been.

I start with a few definitions and some ‘facts’ that all sides in this debate can hopefully agree upon.
– “Subsidies are one of many policy instruments used by governments to attain economic, social and environmental objectives.” (iisd)
– “Energy subsidies, in particular, are often used to alleviate energy poverty and promote economic development, by enabling access to affordable modern energy services.” (iisd)

The EIA, in its analysis, refers to ‘energy subsidies and interventions’ in five categories: direct cash expenditures to energy producers and consumers, tax expenditures via provisions in the tax code, R&D expenditures for increasing energy supplies or improving energy efficiency, loans and loan guarantees for certain energy technologies, and electricity supply programs targeted at specific geographical regions (e.g., TVA and BPA). The discussion in this blog post touches on the first four.

U.S. tax code energy incentives were first established in 1916 and until 2005 were focused on stimulating domestic production of oil and natural gas. Incentives for improved energy efficiency and renewable energy (solar, wind, ….) were introduced starting in 2006 and by 2011 accounted for 78% of a substantially increased amount of federal energy-related tax expenditures in that year. However, it is important to recognize that this large support for ‘clean energy’ was due to passage of the American Recovery and Reinvestment Act of 2009 (ARRA), and did not imply a reduction in tax code incentives for fossil fuels or nuclear energy. To put some numbers into this discussion, CBO estimates that tax preferences (“..special deductions, special tax rates, tax rates, tax credits, and grants in lieu of tax credits..”) in 2011 amounted to $20.5 billion. An additional $3.4 billion was provided in FY 2012 by DOE in R&D support for fossil fuels, nuclear energy, energy efficiency, and renewable energy.

CBO also points out that of the four major tax preferences operative in 2011, only four were permanent parts of the tax code (the energy efficiency part of ARRA expired at the end of 2011 and the tax preferences for renewable energy were scheduled to expire by 2013), of which three were directed at fossil fuels and one at nuclear energy.

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A quick word about nuclear energy: the Atomic Energy act of 1946, following the end of WWII, created a framework for government control of civilian nuclear power plants for electricity generation. Industry was concerned about potential liability in the event of a nuclear accident and the limited amounts of liability coverage initially offered by the insurance market, so in 1957 Congress passed and President Eisenhower signed into law the Price-Anderson Act, which has been renewed several times since, and “..governs liability-related issues for all non-military nuclear facilities constructed in the United States before 2026. The main purpose of the Act is to partially indemnify the nuclear industry against liability claims arising from nuclear accidents while still ensuring compensation coverage for the general public.” (Wikipedia). In its latest incarnation the Act requires the nuclear industry to cover the first $12.6 billion of damages, with costs above that to be covered by retroactive increases in nuclear utility liability or the federal government. Regardless of one’s view of nuclear energy, I believe it is fair to say that a U.S. civilian nuclear power industry would not exist without the Price-Anderson Act.

What is my take on all this, an issue I followed closely through my many years in federal service and still follow? Energy is clearly a driving force in economies, and prominence of nations at various points in history have reflected their energy sources – e.g., the Dutch with wind power in the 1600’s, the British with coal in the 1800’s, and the U.S. with oil in the 20th century. So energy is critically important and U.S. policies to encourage oil, natural gas and coal production were central to America’s emergence as a leading economy and nation. However, the context has changed – we now have well-established fossil fuel industries, supplying approximately 80% of global energy today, and we now understand that combustion of fossil fuels puts large amounts of pollutants and carbon dioxide into the atmosphere. These carbon emissions, which mix into the global atmosphere regardless of where they are generated, cause global warming as they change the earth’s energy balance with the sun and create climate change that seems irrefutable and which we are struggling to better understand. So the world has a conundrum: use of fossil fuels helps improve human welfare in lots of ways, but that use is creating a problem that is a severe threat to the planet’s health. These considerations have led to major efforts to develop and deploy clean energy technologies – improved energy efficiency to reduce our need for carbon-emissive fossil fuels, and renewable energy technologies (solar, wind, geothermal, biomass, hydropower, ocean) that do not emit carbon dioxide during power generation. Nuclear power is also a non-carbon-emitting power source that is receiving increased attention.

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Some people, including President Obama, have called for a phase-out of oil industry incentives, especially in light of unusually high profits recorded by major oil companies such as Exxon and Shell. This seems reasonable, as high oil prices today are providing adequate incentive to these companies. A complicating factor is that smaller, independent producers drill most of the onshore U.S. oil wells today, and are responsible for creating the wells that are delivering increasing amounts of home-grown shale oil and gas that are reducing consumer costs, creating domestic jobs, and bringing some factories back to the U.S. from overseas locations. If jobs and national security are our immediate priorities, then incentives for this domestic production by small producers should be maintained. The hitch is that this should not slow down national investment in clean energy technologies which are critical to our long-term economic and national security interests. This is where Congress has to exercise wise judgement as it sets national energy policy – taking care of today’s needs while investing in the future. The transition from today’s fossil-fuel-dependent world will take time, but it would be irresponsible to not look down the road and make necessary investments today that put us firmly on the road to a sustainable energy future. Without government intervention of this type, “..households and businesses do not have a financial incentive to take into account the environmental damage or other costs to the nation associated with their choices about energy production and consumption…unless the government intervenes, the amount of research and development (R&D) that the private sector undertakes is likely to be inefficiently low from society’s perspective because firms cannot easily capture the ‘spillover benefits’ that result from it.” (CBO). Our current energy pricing system does not take into account the ‘externalities’ of energy use such as public health effects and dependence on other countries for part of our energy needs.

In the end it comes down to values, as reflected in policy and budgets. When I first came to Washington, DC and worked on Capitol Hill I was told quickly that ‘budgets are policy’. I feel strongly that we lack a forward-looking national energy policy, which I ascribe to a failure by Congress to do its job of looking to the future, anticipating issues that will face the country, and taking the necessary steps to begin addressing those issues. When such a policy vacuum exists in Washington states often take the lead out of necessity, and that is happening now. We can clearly do better at the federal level to serve our long-term national interests.

Balancing Environmental Interests and Our Energy Future: Often A Difficult Call

I may be dipping my toe (foot?) in doo-doo by taking on this issue with my natural constituency – environmentalists – but here goes. Two articles in today’s (17 January 2014) Washington Post got my attention and stimulated this blog post.

The first piece, ‘Green groups assail Obama on climate’ (digital edition tile: ‘Environmental groups say Obama needs to address climate change more aggressively’), starts off as follows: “A group of the nation’s leading environmental organizations is breaking with the administration over its energy policy, arguing that the White House needs to apply a strict climate test to all its energy decisions or risk undermining one of the president’s second-term priorities.” It goes on to list a number of ways in which the Obama administration has taken steps to limit carbon dioxide emissions, but the environmentalists’ letter takes issue with the administration for “..embracing domestic production of natural gas, oil and coal under an “all of the above” energy strategy.”

The other Washington Post piece that got my attention was a brief reference to the draft of the soon-to-be-released IPCC (Intergovernmental Panel on Climate Change) report on global warming (‘U.N. cautions against delay on climate change’). It states: “Delaying action on global warming will only increase the costs and reduce the options for dealing with the worst effects of climate change…global warming will continue to increase unless countries cut emissions and shift quickly to clean energy.”

If one reviews my earlier posts in this blog it will be clear that I support a rapid transition to a clean energy future based on energy efficiency and renewable energy. Having devoted my professional career in government to that end, I believe that President Obama ‘gets it’ re global warming and the need for renewables. In fact, I chose not to retire from the U.S. Department of Energy in 2009, when I was more than old enough to do so, because we had finally elected a President who I believed did ‘get it’, after the frustrating years of Bush 43. I believe my trust was well founded based on President Obama’s subsequent behavior, in word and in action, and it bothers me that some of my environmental colleagues apparently see it differently. I may be getting old and you can say that I am getting more cranky and conservative in my dotage, but I don’t think so. I see myself as more aware of the realities of governing, especially after a long career in Washington, DC, and think Obama is doing a good job under very difficult circumstances (yes, I am referring to a dysfunctional Congress). I do see value in keeping the pressure up on a sometimes-too-political White House, but let’s at least acknowledge more often that the guy is doing a good job, and a much better one than Clinton and Gore did in the 1990’s when they faced similar political problems. Obama is finally getting us started on the path we should have been on twenty years ago.

To be more specific: I recognize and regret that the U.S. does not yet have an energy policy that creates the economic environment for a rapid transition to a clean energy future, as is true of a few other countries (e.g., the EU). It is critically needed, but the reality is that creating such a policy ultimately is the responsibility of our legislative branch. All the Executive Branch’s rhetoric can’t change that, although it has to keep pushing as much as it can and implementing as much as it can through executive orders.

One impact already is a significant reduction in power generation in the U.S. using coal, due to its replacement as a fuel by natural gas. This is due to the large amounts of shale gas released by fracking, a technology that I believe is unstoppable (see my blog entitled ‘Fracking: The Promise and the Problems’) and needs careful regulation. Many environmentalists oppose fracking because of the real risks it poses to water supplies, and I share those concerns, but the important upside is that using natural gas instead of coal for power generation puts much less carbon dioxide in the atmosphere. If renewables were ready soon to assume the power generation burden, and our transportation infrastructure was electrified and ready to use hydrogen in fuel cell vehicles (for which the hydrogen was generated from renewables-based electrolysis of water), then down with fracking for natural gas and oil. But that is not where we are today, and fracking and its economic returns will be with us for a while. Lots of work to prepare the way to our inevitable clean energy future still needs to be done. For similar reasons I do not oppose the Keystone Pipeline – I recognize its risks and wish we could avoid its extension, but stopping it is not going to stop Canada from exploiting its tar sands resources. I’d rather have that oil coming to the U.S. and reducing our continuing dependence on imports from other, less friendly countries. Imports are going down but will still be with us for a while until we introduce greater electrification of our transportation fleets.

Lots of other issues come into this discussion, for which I have no time in this blog if I am to keep it to a reasonable length. The bottom line in my head is that we (clean energy advocates, environmentalists) have to do a better job of educating the public about the long-term advantages of a clean energy society (including jobs) and elect representatives in both the House and Senate who ‘get it’ and feel the pressure from home to move us more rapidly in this direction. Ultimately, politicians understand the power of the ballot box if they understand nothing else. One of our tasks is to use that power effectively.

Biomass Energy: An Old and Future Technology

Biomass is defined by Wikipedia as “biological material derived from living, or recently living organisms.” It includes plant material and animal wastes. Combustion of biomass has been used throughout human history to provide heat, ever since the discovery of fire, and is the oldest form of renewable energy (it has an extensive literature). It is still widely used for heating purposes but other ways to obtain useful energy from biomass have now been developed, including gasification and conversion to liquid fuels. Each of these applications and biomass’ significant potential are discussed below.

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A lot of biomass is produced each year in the world, about half in the oceans and half on land. It is biologically-produced matter based in carbon as well as hydrogen and oxygen. Estimated annual production is 100,000 billion kilograms of carbon. An important point to keep in mind is that the chemical arrangements of these organic materials can be changed, an important focus of biomass research.

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On land biomass can be obtained from a variety of sources:

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Wood, in the form of trees, tree stumps, branches, wood chips, and yard clippings remains the largest source of biomass energy today. In many developing countries it is still the only combustion fuel source for domestic use. Other common fuel sources include municipal solid wastes, animal wastes (e.g., ‘cow chips’ or bio-digested manure), and landfill gas (primarily methane and carbon dioxide).

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In recent years pellet fuels, made from compressed biomass. have been used increasingly for heating in power plants, homes, and other applications. Wood pellets are the most common type, but grasses can also be pelletized. Pellets are extremely dense and can be produced with a low moisture content that allows them to be burned with a high combustion efficiency. Further, their uniform shape and small size facilitates automatic feeding. According to the International Energy Agency global wood pellet production more than doubled between 2006 and 2010 to over 14 million tons. In a 2012 report, the Biomass Energy Resource Center anticipated another doubling of wood pellet production in North America within five years.

wood pellets

An important application of biomass is its direct conversion into liquid fuels, or biofuels, that can replace petroleum-based fuels such as gasoline, diesel and jet fuel. These ‘alternative’ fuels fall into two categories, first generation biofuels such as ethanol that are derived from sugarcane and corn starch (and therefore compete with food crops) and second generation biofuels that use as feedstock non-food and low value agricultural and municipal wastes that are not edible. Production of first generation biofuels is well underway in Brazil and the U.S. but second generation production is still limited by high production costs. The problem is the difficulty in breaking down the lignocellulosic biomass that constitutes the bulk of plant matter. Governments and many private sector firms are attacking this problem and 2014 could be a breakthrough year as a number of second generation production plants come on line.

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Ethanol, which is usually mixed with gasoline to produce E-10 (90% gasoline and 10% ethanol) can also be produced by gasification of biomass. Gasification processes use high temperatures in a low-oxygen environment to convert biomass into synthesis (or ‘syn”) gas, a mixture of hydrogen and carbon monoxide. This gas can then be chemically converted into ethanol (C2H5OH) or a wide variety of other C-H-O molecules and fuels.

An emerging and potentially major biomass field is the production of alternative fuels using algae (algaculture). Algae is Latin for ‘seaweed’ and are “..photosynthetic organisms that occur in most habitats. They vary from small, single-celled forms to complex, multicellular forms, such as the giant kelps that grow to 65 meters in length.” ‘Photosyntheic’ refers to algae’s ability to capture light energy to power the manufacture of sugars, carbohydrates composed of C-H-O that can then be converted to other C-H-O molecules. . Algae differ from plants in that they are primarily aquatic.

algae

Interest in algae was triggered by the need for alternatives to petroleum fuels and the world food crisis. Algae produce lipids (a variety of organic compounds) that can be used for making biodiesel, bioethanol, biogasoline, biojetfuel, biomethanol, biobutanol, and other biofuels, using land that is not suitable for agriculture (e.g., land with saline soil). They can be produced using seawater, brackish water, and wastewater, and are biodegradeable. An important, and perhaps critical, aspect of algaculture is that it is claimed that algae farming can yield 10-100 (one claim says 300) times more fuel per unit area than other second-generation biofuel crops. It is estimated that growing enough algae to replace all U.S. petroleum fuels would require only 0.4% (15,000 square miles) of the U.S. land area, or a small fraction of land currently devoted to corn production. Algae crops also have a short harvesting cycle – 1 to 10 days – and so can be harvested repeatedly in a short time-frame.

The biggest barrier to greater use of algae-derived biofuels is the cost of scaling up to commercial production levels. Another concern, for open-pond algae facilities, is contamination by invasive algae and bacteria and vulnerability of monocultures to viral infection. Many schemes for reducing costs and potential contamination are being explored, given the large potential markets available. One obvious target is ground transportation. Another such market is the U.S. military which is already testing biofuels in aircraft and ships. A third large potential market is commercial air transportation. Finally, like all energy sources, biomass has environmental impacts and risks – e.g., water demand and deforestation if land is cleared for biomass production.

A brief word on biochar, a form of charcoal that is created by pyrolysis (low- or no-oxygen heating) of biomass. It is believed that pre-Columbian Amazonians used biochar to increase soil productivity. In addition, biochar has attracted growing attention because of its ability to sequester carbon for centuries (and thus reduce global warming) and its ability to attract and retain water because of its porous structure and high surface area. its production also does not compete with food production.

biochar

In my view, and that of many others, biomass will be a major part of our renewable energy future. It is available world-wide, grows in great and diverse quantity, can be used for direct heating and electricity production via heating of water, can be converted to liquid fuels and other C-H-O commodities, and, if used carefully, has significant potential to reduce greenhouse gas emissions. . The Union of Concerned Scientists has estimated that biomass can provide up to 248 GWe of power generation capacity if fully utilized in the U.S. Current U.S. generating capacity is just over 1,000 GWe. Costs, the major barrier, will come down and our children and grandchildren (and probably many of us) will be traveling in biofuel-powered cars, trucks, trains, airplanes, and ships before too long in the 21st century. It is an exciting option and real possibility that is just over the horizon.