The EPA recently recognized 20 entities in its Green Power Partnership for generating and consuming the most green electricity onsite.
Organizations that utilize onsite green power help expand America’s renewable energy portfolio, improve the nation’s energy security, and reduce climate change impact, points out Allison Bellins, communications director for EPA’s Green Power Partnership. The top five partners are: the Kimberly-Clark Corporation; Los Angeles County Sanitation Districts; San Diego, CA; San Jose/Santa Clara Water Pollution Control Plant, in California; and CalPortland Company. The top five partners consumed and generated more than 535 million kWh of onsite green power, an amount preventing carbon dioxide emissions equivalent to the emissions from more than 70,000 passenger vehicles annually.
Bellins emphasizes that onsite renewables can also provide a number of benefits to the individual host, such as power reliability, protection against price volatility, and a visible demonstration of environmental commitment. In many states, electricity generated with onsite renewable generation may be sold back to the grid at the same price at which power is bought, through a process called net metering, thus improving the financial return for onsite systems, although net metering is often limited to small installations, Bellins adds.
The top 20 Green Partners combined each year consume and generate more than 736 million kWh of onsite green power, equivalent to the amount of electricity needed to annually power more than 61,000 American homes. The list is dominated by private and public California entities. The onsite green power is generated from renewable resources such as solar, wind, geothermal, biomass, biogas, and low-impact hydropower.
“The Green Power Partnership is a voluntary program that encourages organizations to buy green power as a way to reduce the environmental impacts associated with conventional electricity use,” says Bellins.
“Through the partnership, EPA recognizes partners’ market-leading purchases,” she adds. “Our national top Fortune 500 purchasers list and Top 20 onsite users list lets stakeholders see what organizations are setting the bar for green power in the US. Moreover, by recognizing certain partners’ purchases, EPA hopes to spur other organizations to follow in their footsteps by investing in clean, renewable power.”
In a prepared statement, EPA Administrator Lisa P. Jackson praised the partners for setting a standard for the US’ clean energy future. “These companies are leading a nationwide move to the clean energy economy, one that can create million of jobs, reduce our dependence on foreign oil, and protect against global climate change,” she says.
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Photo: Sanitation Districts of Los Angeles County
Joint Water Pollution Control Plant |
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Photo: Sanitation Districts of Los Angeles County
Puente Hills Landfill |
EPA’s Green Power Partnership works with more than 1,100 partner organizations—including businesses of all sizes, government entities, and educational facilities—which voluntarily purchase green power to reduce the environmental impacts of conventional electricity use. The program has been in place since 2001. In total, the partners are buying more than 16 billion kWh of green power each year, equivalent to the carbon dioxide emissions from electricity use of more than 1.6 million American homes.
Biomass at Kimberly-Clark
Kimberly-Clark generates nearly 193 million kWh of biomass power annually, which equates to 7% of Kimberly-Clark’s electricity use in the US. It received top ranking on the EPA’s Green Partners list. “Kimberly-Clark’s number one ranking is a reflection of our commitment to sustainability in our operations,” said Suhas Apte, Kimberly-Clark’s vice president of environment, energy, safety, quality, and sustainability. “Our teams around the globe are continually working to reduce our environmental footprint.”
Kimberly-Clark also was named a 2009 Energy Star Partner of the Year by the EPA for its ongoing efforts to increase energy efficiency and reduce greenhouse gas emissions across its operations. The company is an Energy Partner in the EPA’s Landfill Methane Outreach Program and has received the EPA’s “SmartWay Excellence Award” for leadership in energy conservation and lowering greenhouse gas emissions through EPA’s SmartWay Transportation Partnership. Kimberly-Clark’s Everett, WA, facility utilizes biomass fuel consisting of bark removed from logs in lumber mills, ground-up biomass from clearing operations, and wood debris from construction sites to fuel a cogeneration energy system. The steam from the system generates electricity that is placed on the power grid.
“Some of the green power produced at Everett provided part of the power needs of Sacramento, California, for about 10 years, and now provides sustainable power locally,” says company spokesman Lance Latham.
Wastewater Energy Recovery
The County Sanitation Districts of Los Angeles County (LACSD) has been a leader in many ways over the past century. The agency, which deals in water treatment and solid waste disposal, was the first special district in existence, says Don Avila, a division engineer and agency spokesperson.
The LACSD was formed in 1923, under the health and safety code of southern California, to treat sewage and have a second system to that of the city of Los Angeles, CA. The system treats water from 78 of the county’s 88 cities, serving 28 separate districts, with each one its own political entity joined through legal agreements to share the system. The agency has taken the second spot on EPA’s top Green Partner power lists.
“The energy recovery is first in the world in wastewater,” says Avila. “Our mission statement says we handle both solid waste and wastewater in an environmentally-sound, cost-effective manner. In doing so, we convert waste into resources: reclaimed water, energy, and recycled materials.”
The first time the agency generated its own power onsite was in the early 1970s, when it ran landfill gas through an internal combustion engine that powered a generator and lit a Christmas tree. “It just started snowballing from there,” says Avila.
Now, 54% of the agency’s consumed power is green. Annual onsite green power usage is 171 million kWh. Avila says the agency is about the 20th largest power generator in the state of California, “and we’re not even in the power business. We put out a total of 119 megawatts of electricity. That’s all green energy from biogas, either from landfills or sewage treatment plants.”
That powers a number of operations. The agency encompasses 11 wastewater treatment plants, three operating landfills, three closed landfills, and is involved with two refuse-to-energy facilities. “The most notable is our large Joint Water Pollution Control Plant. It is a 400-million-gallon wastewater treatment plant that operates at about 300 million gallons per day. It generates 22 megawatts of electricity, enough to provide for all of the needs of the treatment plant, making it energy self-sufficient.”
The Power Generation Facility at the Joint Water Pollution Control Plant was built in the mid-1980s to generate power from gas produced through anaerobic digestion of biosolids removed from wastewater.
For the combustion of the digester gas, the combined cycle process utilizes gas turbine generators. Waste heat is recovered from the turbine exhaust, generating steam to drive a steam turbine generator, creating additional power.
The agency has undertaken a steam cycle modifications project to increase maximum plant capacity to 36 MW, more than enough needed to power the treatment plant into the future. The $25-million project will finance replacement of the existing heat exchangers with a higher capacity unit as well as upgrades on other system components. Avila says the agency saves nearly $18 million dollars a year, because it doesn’t have to buy power from the grid, thus ensuring utility price certainty and enabling the agency to sustain low user fees.
“We use not only the power, but the heat from the wastewater treatment for building heating and cooling,” says Avila. “On occasion, we even sell energy.”
The LACSD has served as a mentor for other sanitation districts nationwide, Avila points out. “We were the first in the country to do a steam-to-energy system, where it goes into a boiler, generates high-temperature steam, runs it through a Fuji Electric turbine, and that generates the electricity,” he says.
The agency also came up with another system in which it purifies the landfill gas, which leaves 98% pure methane after pulling out water and impurities, and is then compressed to 3000 PSI and used as fuel for all of the agency’s small vehicles. “The landfill actually generated fuel for our own trucks,” says Avila. “We got a clean air award from the state of California for that, because we pulled out a significant amount pollution from the air by not using gas and diesel.”
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Photo: Environmental Services Dept. City of San Jose
Secondary tank aeration basins: long-shot of secondary tanks |
Avila says there’s a relatively short period of time that the agency has had to wait to reap the return on its investments. “The Puente Hills Landfill was one of the first places where we were going to lay a full, large-scale, gas-to-energy facility and didn’t have the technology to do it,” he says. “We hired private contractors, and we hired a firm that not only financed it, but designed it and built it. We took over operations and paid them back with the money from the energy, and it paid for itself in five years.”
Avila equates the generation of onsite power at landfills to a Native American philosophy of using every part of a hunted animal. “In wastewater and solid waste management, you typically in a landfill have got landfill gas that is generated by the bacterial decomposition of the trash, rises through the landfill, and you can smell rotting garbage from miles away,” says Avila. “That’s why people hated the new dumps, and why they still have problems with some landfills that don’t have good gas collection.”
Historically, that has meant flaring the gas. “It doesn’t take a lot to realize you’re wasting a tremendous amount of energy,” he says. “That’s when landfill operators started looking for alternatives and came up with the gas-to-energy system. So now you’ve got a landfill that, before, burned all of the gas off and is, instead, now generating 48 megawatts of electricity that’s substantially cleaner than alternatives like coal-fired plants.”
The agency’s energy costs are expected to drop over the next few years due to several factors. Among them, it’s anticipated that, by the end of 2009, all of the agency’s direct access electricity needs will be met by the Puente Hills Gas-to-Energy Phase II and the Calabasas Gas-to-Energy facility. Additionally, Renewable Energy Credits (REC) from self-generation facilities can be sold. Based on projected market prices of $10 to $25 per megawatt-hour, REC sales are expected to generate $1.8 to $4.5 million in annual revenue.
Cogen in San Diego
In 2003, San Diego made a commitment to produce 50 MW of renewable energy by 2013. To that end, the city operates a gas utilization facility at its Point Loma Wastewater Treatment Plant. The cogeneration facility is powered by methane gas and generates 4.57 MW of electricity. The treatment plant also utilizes a hydroelectric facility that produces another 1.35 MW of power, which is generated by the 100-foot drop of treated sewage flow exiting the plant into the ocean. The methane gas captured from the sewer system is converted to enough energy to power the entire plant, plus enable San Diego to sell back to the local utility 50% of what is produced, says Tom Blair, the city’s deputy director for energy sustainability and environmental protection.
San Diego’s many efforts netted the number three ranking on EPA’s list of top 20 entities that generate the most onsite green power. The city is also a member of EPA’s Green Power Leadership Club, a distinction given to organizations that have significantly exceeded the federal agency’s minimum purchase requirements. Members must purchase 10 times the partnership’s minimum requirements organization-wide.
Recently, the treatment plant added a 1.2-MW generator peaking unit, which operates on 80% digester gas and 20% diesel fuel, and is the first time an existing diesel generator has been converted into a peaking unit utilizing digester gas. Methane gas produced by a set of digesters at the Metro Biosolids Center and landfill gas from the adjacent Miramar Landfill is captured and converted to produce 6.4 MW of electricity.
Excess digester gas is harvested, cleaned, compressed, and delivered as fuel-to-fuel cells within the city of San Diego, says Blair. San Diego built upon those successes with the North City Water Reclamation Plant, constructed to produce 3.8 MW of energy from excess landfill gas. A third-party partner produces power for the wastewater treatment operations and sells excess electricity to the local utility. The two facilities’ cogeneration efforts produce a total of 10.2 MW, of which half is utilized onsite.
On an annual basis, San Diego generates more than 69 million kWh of renewable power, providing for 27% of its electricity use. San Diego also has 14 photovoltaic (PV) systems installed throughout the region on city-owned facilities capable of producing 1.2 MW—most from the Alvarado Water Treatment Plant, which generates 1 MW of power through its solar panels.
San Diego has been “very active” in energy self-generation for years, notes Blair. “After the oil shortages in the 1970s, we’ve been looking at ways to produce our own energy,” he says.
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Photo: Sanitation Districts of Los Angeles County
Steam turbine at Joint Water Pollution Control Plant |
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Photo: Sanitation Districts of Los Angeles County
Clean fuels facility filling station |
San Diego engaged in major renovations of its gas systems as the Point Loma Waste Water Treatment Plant, starting in 1997. “We were adding all along and continue to look at potential sites all of the time,” says Blair. “We have some closed landfills and are looking at capturing landfill gas there. We currently flare.”
Blair credits San Diego’s elected officials for helping the city move along projects that will propel it to its goal of producing 50 MW power by 2013, which he calls a “significant stretch.”
The return on the investment in the equipment to reach that goal “varies all over the board,” says Blair. “To make the projects cost effective, we’d like to have something in the seven to 10-year range,” he says. “Solar systems are tough, so we combine energy efficiency improvements with solar so net savings are better.”
Onsite Green Power in San Jose
The San Jose/Santa Clara Water Pollution Control Plant generates 56% of its energy needed onsite, with biogas as its resource. Onsite green power usage is 52 million kWh. Methane gas is collected through the plant’s own treatment process, as well as from an adjacent landfill, which is then converted to electricity.
“Treatment plants in our area discharge into the San Francisco Bay, which is an extremely sensitive ecosystem, so our permit has very high treatment standards,” says Jennifer Garnett, the spokesperson for the environmental services department of the city of San Jose, which co-owns the treatment plant with the city of Santa Clara.
“We treat to a tertiary level of treatment,” says Garnett, adding that doing so is an energy-intensive process. “We’ve been motivated for quite some time to reduce our energy costs by using the methane gas we produce onsite to power the plant.”
The San Jose/Santa Clara Water Pollution Control Plant is currently in a master planning process for rebuilding the treatment plant, now more than 50 years old. “It’s a 30-year plan for how we will rebuild the facility and use the surrounding land as part of that process,” she says. “We’re looking to make the plant even more energy efficient as part of our environmental goals.
“One of our goals is to recycle or beneficially reuse 100% of our wastewater,” says Garnett. “We have a strong environmental vision in place, and we want San Jose and its facilities to be in a leadership position for the nation and the world.”
Future plans center on negotiations with a company formed to bring a European technology to the US, that uses a dry anaerobic process converting organic material into energy, she explains. “For wastewater treatment, the biocells are very wet, and they’re put into digesters which generates methane,” she says. “In this case, we would start to collect organic material that’s relatively dry, put it into enclosures, and convert it into compost and energy.”
The cities also are considering using some of its land for solar panels. Among the challenges in producing energy onsite are the technical ones involved in maximizing efficiency and collecting the source of material, says Garnett. “Related to the organics situation, we need the infrastructure in place to do that collection, and certainly there are investments requiring public-private partnerships,” she says. “I believe we’re ready and willing to face those challenges.”
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Photo: Sanitation Districts of Los Angeles County
Power plants at Puente Hills Landfill |
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Photo: Sanitation Districts of Los Angeles County
Clean fuels facility at Puente Hills Landfill |
Garnett says there’s been a favorable return on the investment in the equipment it takes to generate energy onsite. “It’s paying off for us, because it’s using the available energy source,” she says. “The plant is the biggest energy user of all of our facilities combined, and we’re saving millions of dollars, on an annual basis, on our power bill.”
One of the benefits of generating onsite energy is the ability to keep rates low, Garnett points out. “If our operational costs are lower, then we can keep our cost for ratepayers down,” she says. “Not paying as much in electricity costs helps us save overall city energy costs.”
The cities are mindful of the effect of greenhouse gas emissions, says Garnett. “One of the things we’re trying to do is keep greenhouse gas out of our landfills, and by capturing that methane gas, we’re contributing to climate action. There’s an overall sense of the city trying to view these byproducts—things that would go by the wayside—more as resources.”
Desert Wind
Established in 1891, CalPortland is the oldest continually producing Portland, OR, cement company west of the Rocky Mountains, and is now a diversified regional construction and building supplier operating in western North America. The company has operations throughout Washington, Oregon, Nevada, Arizona, and California. CalPortland generates 50 million kWh of wind power annually and is the largest onsite wind power project of any organization in the Green Power Partnership. The company’s green power comprises 11% of its electricity use.
CalPortland ranks fifth on EPA’s Green Partner list. The company’s strategic location in Glendora, CA, where the wind in the Mojave Desert serves as a viable resource—combined with the company’s philosophy on the importance of renewable energy generation—led the company to install eight 3-MW wind turbines on its property along with two 1-mile-long transmission lines through Oak Creek Energies.
“We want to take advantage of the resources in our backyard,” says Steve Coppinger, the company’s director of energy services. “One of the advantages of having onsite generation is that it’s close to the road source. Traditionally, generation is so far from the plant and the roads, there is a lot of losses in the lines, but by having them onsite, it eliminates those losses and also improves efficiency.”
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Photo: Sanitation Districts of Los Angeles County
Outside of power plant at Joint Water Pollution Control Plant |
Coppinger says CalPortland is unable to put excess wind power back on the grid because the lack of transmission line capacity. “We have to consume everything that the generators produce on our plant, nearly 24 megawatts, which is near what our load is for our plant,” he says. “When the wind is blowing, we can power an entire plant with wind.”
Coppinger says his company would like to go to the grid with any excess power, “because if we shut a part of a plant down during a particularly windy time, we have to manage that excess wind at this time. It affects our operations in that if we plan to shut down one of our large grinding mills, and, if a windy day is projected, we will run it during the day to take advantage of that wind and take it down on a day where it’s not so windy, so we can optimize the use of wind.”
That presents operational challenges. “When you cut back on production with the economy being what it is, there is more wind generated than you’re able to consume,” says Coppinger. “That’s why it’s important to be able to go back on the grid so other people can take advantage of a renewable source. When the economy gets fixed up, we expect we’ll be able to use every bit of wind that is generated.”
CalPortland continues to explore other options such as solar energy and increasing the number of wind turbines on its property, says Coppinger.
The Rest of the List
In addition to these recognized Green Partners, the Top 20 list also includes; Nassau County, NY; BMW Manufacturing’s Greer, SC, facilities; San Francisco, CA; Kohl’s Department Stores; Wal-Mart’s California and Texas facilities; Portland; Johnson & Johnson; US Air Force; Macy’s California and Hawaii stores; University of Iowa; Ann Arbor, MI; Safeway Inc.; Sierra Nevada Brewing Company; Gresham, OR; and Alameda County, CA, GSA facilities.
Although onsite green power generation has its many benefits, there are challenges, according to the EPA.
The federal agency points out the following factors that must be considered before embarking on the installation of onsite green power, which:
- Might be limited to states where financial incentives and high-energy costs coexist, in order to achieve a financial return on the system within a specific timeframe
- Can require a high upfront investment
- Requires maintenance over the life of the system
- Involves more upfront planning and project management resources
- System owners must retain RECs associated with the system in order to make environmental claims.
However, there are an increasing number of entities using onsite power for some or all green power activities, demonstrating compelling financial and environmental opportunities nationwide, says Bellins. The Return on Investment (ROI) varies with each technology, geographical location, and opportunity presented by project sites.
The federal agency points out that one option for generating solar electricity onsite is to enter into a Solar Power Purchase Agreement (PPA). PPAs are financial arrangements in which a third-party developer owns, operates, and maintains the PV system, and a host customer agrees to site the system on its roof or elsewhere on its property.
The host purchases the system’s electric output from the solar services provider for a predetermined period. This financial arrangement provides the host customer with clean, reliable electricity at an agreed-upon price schedule. Because the system is owned by the provider, the host customer is able to avoid high capital costs, as well as operations and maintenance requirements, the EPA points out. Solar PPAs have helped to drive a dramatic increase in the use of solar electricity by Green Power Partners, particularly in the retail sector, according to the federal agency.