BioCycle March/April 2015
St. Landry’s Parish, Louisiana: Expanding RNG Fueling Facility
The St. Landry Parish Solid Waste Disposal District installed a vehicle fueling system in 2012 to clean and condition its landfill biogas for use in its sheriff and public works vehicles. The landfill receives 275 tons/day of MSW, and generates 300 scfm of gas with a methane content of 55 to 58 percent. The District purchased a BioCNG skid-mounted system that includes hydrogen sulfide, VOC/siloxane and carbon dioxide removal, and chilling. It uses a fast-fueling, single compressor fueling unit. The system is scaled to treat and compress 50 scfm/day of gas and can produce up to 250 gasoline gallon equivalents (GGE)/day. The remaining biogas has been flared. The St. Landry Parish BioCNG Vehicle Fuel Project received the U.S. Environmental Protection Agency’s Landfill Methane Outreach Program 2012 Project of the Year award.
Recently, the district announced a plan to expand its fueling capacity by installing a second BioCNG system (also rated at 50 scfm/day) and a remote CNG fueling station. The expansion is part of a contract between St. Landry Solid Waste and Progressive Waste Systems. In exchange for continuation of its existing waste hauling contract with the district, Progressive Waste has agreed to purchase new CNG-powered trucks, and will have access to the increased BioCNG generated from the expanded system. The project will also provide BioCNG fuel to additional St. Landry Parish clients. The District can transport the BioCNG to the off-site fueling location in a compressed gas tube trailer.
Wooster, Ohio: Degree Program In Renewable Energy
The Agricultural Technical Institute (ATI) at The Ohio State University (OSU) offers an Associate of Science degree program in Renewable Energy, with two areas of specialization: 1) Bioenergy, which focuses on generation of biogas from organic material from agricultural, industrial, and municipal by-products and waste; and 2) Solar and Wind Energy, which focuses on energy production from solar panels, wind turbines, and other technologies. The Associate of Science degree allows students to complete approximately 50 percent of the requirements for a Bachelor of Science degree in agriculture at OSU. Students in the Renewable Energy program complete a paid industry internship at such firms as biogas generation plants, wind farms, solar panel manufacturers, research facilities and municipalities.
According to ATI, career prospects in what is anticipated to be a $630 billion renewable energy industry in 2030 include: Equipment installation and service technicians; Environmental engineering technicians; Bioenergy plant/system operators; Energy facility manager; Renewable energy equipment sales; Research laboratory technicians; and Water and waste treatment system operators. The ATI’s specialized facilities provide numerous hands-on opportunities for students and include: Renewable energy laboratory with small-scale biodigesters and wind and solar trainers; Fully-operational, 550,000-gallon biodigester; Bioenergy research laboratory at the Ohio Agricultural Research and Development Center, located adjacent to the Ohio State ATI campus; a 1,700-acre farm, with dairy, beef, swine and equine facilities and 900 acres of crops; and a 21,000-square-foot greenhouse complex.
Pixley, California: AD Biogas Helps Power Ethanol Plant
An anaerobic digester constructed adjacent to the Calgren Renewable Fuels ethanol plant in Pixley held its grand opening in February. The digester, designed by DVO, Inc. and built by Regenis, processes 55,000 gallons of solid and liquid manure daily from Four J Farm Dairy, along with about 10,000 gallons/day of grease, renderings and food processing residuals. The biogas is used by the ethanol plant to replace natural gas; currently biogas provides about 5 percent of the total natural gas combusted. The Calgren facility produces about 55 million gallons/year of ethanol.
Gwynedd, North Wales, United Kingdom: Comparing Ad Feedstocks And Ghg Emissions
In a paper recently released in the journal, Global Change Biology Bioenergy, researchers from Bangor University in the United Kingdom and the Thünen Institute in Germany conclude that crop-biogas and liquid biofuels are at best inefficient options for greenhouse gas (GHG) mitigation, per hectare of land used and per public subsidy required. The researchers evaluated the environmental balance of various bioenergy options introduced into a typical arable farm rotation. They applied farm models and consequential life cycle assessment to compare the environmental performance of: 1) Electricity and heat production from on-farm biogas plants fed by either maize, grass, pig manure or food waste; 2) Bioethanol and biodiesel production from wheat and oil seed rape, respectively; and 3) Heat production from Miscanthus pellets.
While GHG emissions from indirect land use change can outweigh the GHG mitigation achieved by fossil energy replacement for crop-biogas and liquid biofuel options, anaerobic digestion of manures and food wastes avoids emissions arising from manure storage and composting of food waste, even before the GHG mitigation of fossil energy replacement by the biogas produced is accounted for. However, care is required to minimize ammonia emissions during storage and land application of the digestate “biofertilizer” produced along with biogas in anaerobic digestion plants.
“Whilst subsidies are necessary to correct for market failure and develop vital renewable energy sources, it would seem sensible to link such subsidies with environmental sustainability criteria to ensure that they efficiently contribute to overall net public good,” notes Dr. David Styles of Bangor University, who led the research. “Our results highlight the importance of applying life cycle assessment to comprehensively evaluate the environmental sustainability of bioenergy options, capturing hotspots such as indirect land use change associated with food crop displacement, the climate effect of biomethane leakage, and ammonia emissions arising from digestate storage and spreading.”
Edinburgh, Scotland: Celtic Company Claims Whiskey Waste First
Draff, the sugar-rich kernels of barley that are soaked in water to facilitate the fermentation process necessary for whiskey production, and pot ale, the copper-containing yeasty liquid left over from distillation, have long posed a disposal problem for distillers worldwide. Now, using an abandoned process called Acetone-Butanol-Ethanol (ABE) fermentation first developed in the United Kingdom a century ago, Edinburgh-based Celtic Renewables is producing biofuel capable of powering cars from residues of the whiskey industry. ABE fermentation had died out in competition with the petrochemical industry, but biobutanol is now recognized as a direct replacement for petrol. The Scottish company is seeking to reintroduce the process to Europe for the first time since the 1960s, using the millions of tons of annual whiskey production residues as its raw material.
In partnership with Ghent-based BioBase Europe Pilot Plant, the first samples of biobutanol were produced in February. Celtic Renewables, a spin-off company from the Biofuel Research Centre at Edinburgh Napier University, spent the last year developing its industrial-scale process in Belgium as part of a $1.5 million program funded by the U.K.’s Department for Energy and Climate Change (DECC) under its Energy Entrepreneurs Fund. The ABE process also yields green chemicals and high-grade animal feed, according to the company, which is seeking funding from the Department for Transport’s advanced biofuel demonstration competition. Winners will receive funding of up to $18 million over three years to build a biofuel facility that should be operational by December 2018. Tullibardine, a Scottish whiskey distillery in Blackford, Perthshire, has been supplying Celtic Renewables with the raw materials. The distiller has the capacity to provide about 7,200 tons of draff and 528,000 gallons of pot ale annually, which are currently spread on agricultural fields, turned into animal feed or discharged into the sea under license, all at significant cost.
Sacramento, California: Readoption Of Low Carbon Fuel Standards
The California Air Resources Board (CARB) held a public hearing in February on the proposed readoption of an updated low carbon fuel standard (LCFS), a renewable fuels incentive program in California implemented by CARB to reduce the average Carbon Intensity (CI) value of the transportation fuel mix sold in California. The goal is to achieve a 10 percent reduction in average CI of transportation fuel used in the state by 2020. The LCFS is based on a “well-to-wheel” model (CA-GREET) that measures the greenhouse gas (GHG) impact of biomass cultivation, biofuel production, transportation and distribution. Under the rule, production facilities have to register with CARB and are assigned a default CI value for their fuel. The standards went into effect in 2010, however due to legal actions that were concluded in 2013, CARB has to readopt the regulation to address the court’s ruling. The Board took the opportunity during the readoption process to update the regulations and implement improvements to the program, according to EcoEngineers, a consulting firm and project developer in the renewable energy sector. The changes include: Cost containment measures, including a price ceiling of $200/CI credit; Two-tiered system for applying to use pathways, along with automation and combined steps to simplify the approval process; New model to create pathways for fuels (GREET 2.0) that allows for greater precision when calculating GHG emissions; and Provisions to allow obligated parties to generate CI credits through improvements in their processes and energy use. The final CARB hearing to approve or deny LCFS readoption will take place in June or July 2015. If approved, the effective date will be January 1, 2016, at which point all GREET 2.0 pathways that have been accepted will be eligible for CI credit generation.
London, United Kingdom: Digester Developer Signs Long-Term PPA
Tamar Energy, a renewable energy company, focusing on anaerobic digestion and offering a range of composting services, signed a long-term Power Purchase Agreement (PPA) with EDF Energy at the end of 2014 for Tamar’s current 11 MW generation portfolio. The long term PPA covers the company’s first five anaerobic digestion plants (see “Expanding AD Capacity In The UK,” March/April 2014 for background on Tamar and its facilities). “Securing the PPA with EDF Energy, the UK’s largest producer of low-carbon electricity, is an important achievement for the UK’s AD sector, proving the value of AD’s base load generation in the market over the long term,” noted Willie Heller, Tamar Energy’s Chief Executive.