Letter to Mayor Verner on the Sustainability Plan for Spokane
The current partners of the Wheelabrator waste-to-energy (WTE) burner located in Spokane, Washington, should consider utilizing advanced technology including gasification and fast pyrolysis. These technologies are becoming available and would be more effective in addition to serving the city well in regards to revenue streams, job creation, consideration of environmental concerns, and value to rate payers. While the plant does reduce the volume of waste and produces energy, it is neither as clean nor efficient as responsible stakeholders should expect. Additionally, because of the current technology implemented the electrical energy produced does not receive many of the environmental values (credits) attached to renewable energy. For more on current developments in the industry there is information available at www.enersoltech.com
to increase perspective.
Spokane has a major advantage over other WTE facilities because they were able to secure a long-term high value electrical purchase agreement, which pays as much as twice the going rate of retail power sales. The contract also allows for increasing the contract sales volume based on technology including efficiency improvements like gasification and fast pyrolysis. For various reasons including maintenance and repairs the burner runs at less than eighty percent of its electrical generation capacity of 26 megawatts/hour annually.
To demonstrate the feasibility and attributes of a particular technology to process a variety of waste streams I propose a clean green to energy project. The project can be partnered with Spokane's existing collection system at the transfer station or stand-alone with its own collection system. One quality of utilizing these technologies is to substantially help reduce tipping fees, which can keep energy dollars working in the community and create new jobs. At current electrical rates coupled with renewable energy tax credits the project could produce enough heat (for steam turbine operations) to allow for commercial biomass suppliers to realize profits for delivered materials. This process would allow for an economical alternative to manage bluegrass straw, residue from direct cropping systems and other field burning which would alleviate many of Spokane's air quality problems during the late summer months. Within a fifty-mile radius of Spokane there is substantial annual biomass, which can be effectively harvested (Google-Washington State Biomass Inventory).
This part of the project would be able to start operations early every Spring and conclude when biomass levels become too limited in consideration of economies of scale. At this point the site would transition to sorted municipal garbage, including recycled material, and tax credits would still be available. With the recent passage of House Bill 2165 by the Washington State Legislature there may be opportunity to integrate some of the gains from this new legislation into operations at the waste to energy site.
There are many successful biomass conversion projects, which have been implemented by municipalities and at other locations. The city of St. Paul, Minnesota, has for several years used biomass to supply their heating and cooling needs. Seventy percent of all their energy requirements come from biomass collected within a seventy-mile radius of the project site. For more information on their success go to www.districtenergy.com
. Middlebury College in Vermont has also clearly arrived in their quest to become a leader in biomass conversion, reviewing information at www.blogs.middlebury.edu/biomass
should invigorate interest in the biomass conversion industry with leaders here in Spokane. The Mount Wachusett Community College of Massachusetts has developed their program in partnership with several stakeholders with remarkable local success, and there are many others.
With the regional discussions ongoing with the Bonneville Power Administration (BPA) and in consideration of the post-2011 energy efficiency policy there are many advantages to implementing an aggressive energy efficiency program utilizing either gasifier or pyrolysis technologies now. Energy efficiency is valuable to utilities because it reduces total load, reduces peaks and is appealing to end-use consumers, among other reasons. The City of Spokane could be in a good position to opt-in with the Avista Corporation as a third party and plan ahead for rate increases, state requirements to procure all achievable cost-effective energy efficiency, future limits on the amount of power which can be purchased at the Tier 1 rate and cost of purchases at the Tier 2 rate. The city would be a direct beneficiary of this proactive participation.
Thousands of local residents annually haul and deliver clean green material to various sites while paying a thirty-five dollar tipping fee to the City of Spokane. Fees are based on actual green weight for over forty thousand tons of material each year. The city provides personnel at the collection sites and then defers to Waste Management to haul this valuable renewable fuel away. The city could keep these energy dollars and generate additional revenue delivering to the project site and be paid for the tonnage. These dollars saved could be re-invested in expanding site operations to process more municipal garbage and other waste including material from the medical community, sludge from the wastewater treatment facility and waste vegetable oil (WVO) from our local restaurants. The dollar amounts saved we are talking about here are in the millions of dollars and would provide a net benefit to air and water quality (WVO will become more problematic to the waste water treatment facility in maintenance and capacity as the population in the city and environs continues to expand). For more on the potential of pyrolysis one may become more informed by perusing the website for biochar www.biochar-international.org
Further, the opportunity exists to process biodiesel and biogas (AKA, syngas) in addition to developing an industry for biochar as being investigated by Washington State University and the Pacific Northwest National Laboratory. These two biofuels, with the potential of producing a methyl-ester from some of the 1.1 million gallons of WVO available annually in a one hundred mile radius of Spokane, will be useful in developing our energy security with reliable and locally produced biofuel for all kinds of vehicles operated by the City of Spokane and the Spokane Transit Authority. Additionally, there is one thousand tons/day of oilseed crushing equipment in storage at the Spokane Industrial Park. This capacity could come on-line if a biorefinery was available. Farmers could grow oilseed crops regionally and have a location near in consideration of transportation costs. An expansion of niche markets and cottage industry would occur in direct relation to the value-added products associated with the clean green energy project, oilseed meal, and the high oleic base stock (HOBS) resulting from the production of biodiesel.
If the city decides to expand their involvement in new technology at the WTE site substantial monetary benefit can accrue in the difference between the rate currently paid per megawatt/hour generation capacity (26 megawatt/hour) and renewable energy generated and paid at the eleven cent/kilowatt contract value. A partnership with a utility company may be advisable in respect to the dollar value of renewable electric energy produced outside of the current contract with the City of Spokane.
The city now pays over 2.4 million dollars a year to haul ash from the WTE site to the other side of the state. New technology and a better system for sorting the waste stream can result in savings. There may be a point in time when ash from Spokane has a different classification due to contaminants, which will result in a higher fee charged at the landfill used at this time. In fact, no land filling will be allowed beyond 2020 in Germany and the European Community is expected to enact a similar ban. A great deal of the profit from the WTE plant goes to ash transport and tipping fees at the landfill site.
A relatively recent development proposed for solid waste gasification is the plasma arc converter. Although there are many variations, a typical plasma arc converter uses an array of plasma torches to generate temperatures in the reactor of more than 5,000 degrees centigrade.
This extremely high temperature, coupled with a gasification environment in a closed system, has shown potential in small laboratory test units to achieve a very high efficiency in decomposing the organic fraction of the waste to syngas, while generating a slag material from the inorganic and inert fraction. The slag has potential as a substitute ingredient (with sequestration benefits) in many building materials, including concrete structural elements (wall panels and blocks, etc.) and asphalt. This process can also be used to process medical waste, wastewater treatment facility sludge and other materials we need to permanently remove from the environment and food chain. Metals exposed to the process are returned to their elemental form and can be collected for recycling. Plasma-arc gasification does have significant challenges in respect to the cost of electricity and other variables. As technology improves and costs are re-examined this technology may be better positioned to contribute when compared to the ratio of the amount of usable energy acquired from a particular energy resource to the amount of energy expended to obtain that energy resource (eMergy).
This said, refractory gasification and fast pyrolysis do have several advantages and new technology has been developed very recently to operate at higher temperatures, which reduces ash and sequesters carbon. The syngas produced from the waste destruction reaction is a relatively clean energy source and the plant may generate lower volumes and less troublesome air emissions overall. In a typical pyrolysis process a relatively low volume of air is introduced into a reactor vessel, resulting in the waste decomposing into certain gases ( methane, carbon dioxide and carbon monoxide), liquids (oils/tars) and solid materials (char). The proportions are determined by operating temperature, pressure, oxygen content and other conditions. Because there is little to no air or oxygen available, the waste does not combust as it breaks down (there are no flames). When the amount of air in the process is less than that required to support combustion, but greater than in a pyrolysis process, the process is termed gasification. This process is typically used to achieve a different balance of the gaseous by-products, mainly the production of a hydrogen (H)-rich gas with smaller quantities of carbon monoxide (CO), methane (C14) and carbon dioxide (CO2). The refined gas, primarily H and CO2, is termed syngas and has many direct applications such as powering a turbine to produce electricity and potentially for use as a feedstock to produce alternative vehicular fuel (ethanol), or other chemical compounds. Most of these processes require an external heat source under normal conditions. This is usually hot, clean air from the heat exchangers downstream from the syngas production unit.
As these technologies become more widespread municipal subdivisions and federal leadership should take care in evaluating any conversion or plant upgrade to an existing system. This includes; updating their long-term Solid Waste Management Master Plan, waste composition data and generation forecasts and assessing how alternative technology may fit in the community, and dealing with technology and economic risk. Some financing of this and other aspects of the project may be funded using Clean Renewable Energy Bonds (CREB), state programs and private investment.
Another area a solid sustainability plan could deploy in is with the operation of the jail, which is a large expenditure annually. The city should have a community garden program on vacant lots owned by the city. These gardens could also be placed on rooftops and or in community greenhouses. The work crews from the Geiger Correctional Facility or the county jail should be allowed to work on these gardens and the produce distributed to the jail/Geiger to lower food costs and to agencies in Spokane, which feed the homeless. A corrections officer or a probation officer would supervise the work crews.
Further, in the Fall the gardens should be open to the low-income public to "glean".
Instead of incarcerating those owing unpaid fines and court costs (a substantial burden with restitution) the non-paying or the willing should be allowed to work in the community gardens to pay off fines and or court costs. This would require a change in the law regarding legal financial obligations, which is State Law. It might require a Memorandum of Understanding with the federal government, as wages earned in the program would not be counted for income purposes against persons on welfare since they are not receiving the money. These resources should also be made available to individuals within the Spokane County Juvenile Court system as potential sites for juveniles to work off their community service hours.
The benefit of this is a reduction in the cost to the city to house inmates currently at nearly one hundred dollars a day per individual, making more room in the jail. There can be a marked reduction in the cost of food to those fed in jail and this provides a charitable revenue stream to the agencies feeding the homeless which will reduce the amount of money the city would give to these agencies. Providing incarcerated individuals with an opportunity to have a feeling of accomplishment may help them develop self-esteem and move them into the workplace.
While at the new YMCA building recently it was noted there is a substantial area of the roof east of the swimming pool with a wide set of stairs to access the roof. Elevators are available to the second floor, which can be used to assist in moving materials and produce to and or from the roof. The area is recessed about seven feet below the main roof area for plant protection from wind although full sun is available all day. A water supply is close by and substantial carbon dioxide enriched air from the YMCA/YWCA ventilation system could be adapted. Placing mats down for ingress and egress to the garden area achieve safety of the roof membrane. A chain link fence could be installed to protect against fall hazard for the hydroponic garden area which would be the equivalent of over one half acre of productive garden. It is a fact that artificial light is not needed to have a very successful outdoor hydroponic garden, albeit yields are reduced.
The hydroponic garden would be drained in the late Fall after harvest to reduce weight load for snow accumulation. The cities many garden clubs including the Washington State Master Gardener program, www.spokane-county.wsu.edu
, could assist in operations which will lead to more familiarity with the YMCA and YWCA facility by those in the community. As our demands on arable land increase due to population growth and other factors the need for proactive leadership can realize vertical farming and small plot gardening in the urban sector. Projects can be funded from the American Recovery and Reinvestment Act and LEED (Leadership in Energy & Environmental Design) credits may apply.
The Spokane area has been historically a diverse and productive fruit and vegetable crop-growing center due in part to the length of the growing season, soil tilth, and a population experienced with this type of agriculture. Returning to some of our former self-sufficiency in growing more of our own food would bring many advantages. This includes building an effective network of gardening spaces, which will increase economic vitality, connect people to the natural world, promote individual and community well being and sustain natural systems. A strategically designed green infrastructure can retain and attract businesses, encourage new housing, increase the local tax base, provide venues for civic life, cultivate an environmental ethic among urban residents, help manage storm water, and increase the health of residents. For more on this potential there are many resources to peruse at www.greenroofs.com
This concept could be utilized as a model in consideration of a Spokane Roof Top Garden Inventory, small plot gardening programs, developing substantial savings and utility for the City of Spokane and reinforcing the Mayors Sustainability Plan.
Thank you for your consideration.
Dan Lambert, Bioenergy Consultant
Agriculture and Rural Caucus