Energy Innovation: Biogas Enjoying the Last Laugh
- July 19, 2013
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Biogas was not mentioned once in Al Gore’s 2007 documentary An Inconvenient Truth, and at the time the now failed solar firm Solyndra was negotiating a $535 federal guaranteed loan, not the US Department of Energy, EPA or USDA even offered information about biogas on their websites. On the rare occasion an article about biogas appeared in the media, it was filled with lots of toilet humor about flatulence or manure. These writers seemed to share a joke with their readers that biogas was not to be taken seriously. After all, sometimes the musical fruit does not make one toot, how reliable could it be? It was ridiculous to consider powering a modern nation with the blue flame of fraternity prank fame.
“Biogas turns liabilities into assets.”
Since that time, biogas has quietly worked its way into the mainstream awareness in the United States, the federal agencies that once ignored it now offer grants for biogas projects and several states offer incentives and rebates once reserved only for solar, yet what takes place inside a biogas plant remains deeply mysterious to most. It is this lack of understanding about the process and the physical properties of biogas has led to a lot of confusion among the media, public, investors, lawmakers and planners about how to best utilize biogas in modern urban planning. For example, it is a popular misconception that manure is required to produce biogas, when in fact manure produces little biogas per pound compared to other feedstocks. Ironically, ordinary lawn grass produces some of the highest yields per pound. So yes, you could indeed run your lawnmower with the clippings from a previous cutting. And the fallen tree leaves that cost municipalities millions every year for clean-up and disposal provide an ideal carbon source. Biogas turns liabilities into assets. Proving that even in the densest urban environments, nature is the best project planner of all.
“Nature is the best project planner of all.”
The single-celled microorganisms that produce biogas are among the oldest life forms on Earth, remaining virtually untouched by Darwin since the planet’s carbon cycle was established some 3.5 billion years before its oxygen atmosphere. These microorganisms are not bacteria, they are a different breed in the microscopic animal kingdom called Archaea. Unlike animals that require oxygen to live, archaea require the complete absence of oxygen. It is important to understand archaea, like us, are more energetic and productive with a balanced diet. Coincidentally, what archaea consider a balanced diet are what we consider waste. The most disgusting leftovers from the back of the fridge, the foulest-smelling rotten food and, yes, raw sewage are the archaea’s delight.
One reason biogas has taken so long to get noticed is that most biogas plants in the US are at rural dairies or concentrated animal feedlots, municipal wastewater treatment plants or bioreactor landfills, rarely seen by most people. These plants have important benefits to waste management, odor control and water quality, but disregard many of the advantages of biogas. Most significantly, they eliminate any revenue stream from fertilizer replacement that is potentially more valuable than anything that can be done with the gas. These larger plants are also incapable of responding to any variation in waste volume, and must lock waste providers into long-term contracts for their financing. Eliminating any incentive for conservation as they eliminate competitors.
By comparison, biogas is ubiquitous in Sweden. Swedish cities fuel their transit bus fleets with biogas and the country is home to the world’s first biogas commuter train. Swedes can buy biogas at filling stations for use in bi-fuel cars that run on natural gas within cities and switch to liquid fuels for long distances. Sweden and other European countries rely on a larger number of smaller, distributed biogas plants close to or in residential areas. There are important advantages to this, since smaller plants closer to waste sources and end users for their energy save energy by shortening transportation and transmission distances. As much as 75% of the energy at remote coal and natural gas power stations can be lost as heat out the smoke stack. Having power generation near homes and buildings allows the capture of waste heat from generators to be circulated through district hot water and steam systems, turning 40-50% efficient generators into 95% or even 100% efficient combined heat and power stations. This is an important consideration when it is argued that renewable energy will never replace fossil fuels, when three-out-of-four fossil BTU’s are wasted.
This decentralized model presents a historic opportunity to not only undo the waste and environmental destruction of a century of centralization, but create the ever-elusive green economy replacing the nation’s energy-intensive, Reagan-era wastewater infrastructure with modern and efficient waste-to-energy systems. Germany, for example, between 2004 and 2010 added 1,750 biogas plants creating 21,660 jobs.
There are no technical reasons to not already be following these European examples, the barriers to widespread biogas use in the US are man-made. What holds the United States back is not an orchestrated conspiracy by fossil fuel lobbies or political gridlock, it is decades of inertia at all levels of government that both sides of the aisle all-to-eagerly participate in. Ten years passed between Sweden’s first biogas bus system in Linkoping in 1997 and the US DOE first listing biogas on its website. And yet five years into the Obama Administration the United States has yet to put the first biogas transit bus in service.
It is my prediction every household in America will use biogas by 2050. Home scale biogas for cooking and small amounts of summertime electric, and neighborhood or building scale biomass boiler or gasifier for heating and wintertime electric. It is my hope the United States will not only catch up to, but surpass even Sweden’s state-of-the-art waste-to-energy infrastructure. This hope is based on the fact the solar panel generation, the children of the ‘70’s are beginning to retire and are being replaced by younger, more forward-thinking people better connected in real time with the rest of the world. Not only in government, but today’s young entrepreneurs with a healthy disrespect for big, slow-moving establishments will soon take on the multinational environmental engineering firms that manage American public works. I predict creative hacks will be found around the long-term plans and purchasing agreements that keep us from moving in a new direction. These newcomers don’t view biogas as a joke, they see it as the great opportunity it is to make the world a better place.