Thursday, September 13, 2012
By Hannah Guzik
A bio-digester could convert thousands of tons of horse manure into energy in the Ojai Valley, helping to keep the Ventura River Watershed clean and reducing greenhouse gases, a study has found.
The community group Waste 2 Energy has completed the first part of its yearlong study on the feasibility of building a bio-digester in the Ojai area and will present the results Monday from 7 to 8 p.m. at the Matilija Junior High School Auditorium, 703 El Paseo Rd.
“We have a definite waste problem and we have to be responsible for the waste we create,” said Bill O’Brien, a civil engineer and W2E volunteer. “I think part of this is just about being a steward of our environment. We’re just trying to take that waste and make something useful out of it.”
The anaerobic bio-digester would convert horse manure, farm waste, landscaping clippings and food scraps from restaurants and schools into methane energy, fertilizer and compost. The methane gas could be burned for heat or used to turn turbines, creating electrical energy that could be sold.
The first portion of the feasibility study, begun in January, found that the Ojai Valley has enough waste to make a bio-digester practical, O’Brien said. A bio-digester would use 50 tons per day of waste, with 23 tons coming from horse waste, 6.3 tons from horse bedding, 1.5 tons from food waste and 19 tons from green waste.
“The study confirmed there’s enough manure to make this work,” O’Brien said. “That’s what’s hard for people to believe — how much horse manure there is and how much food waste. Right now, most of it’s just going to a dump.”
Much of the waste in the Ojai Valley ends up in the Toland Road Landfill in Santa Paula, although some is composted, he said. But before it can be disposed of, runoff from waste — especially horse manure — can contaminate the Ventura River Watershed, posing environmental problems, according to W2E.
Area environmentalists are hoping to dramatically curb the amount of animal waste that flows into the watershed, because it causes algae and bacteria to proliferate, resulting in lower oxygen levels in the water and harming wildlife, including the endangered steelhead trout.
New mandates from the Los Angeles Regional Water Quality Control Board may soon require area landowners with horses to reduce the amount of manure on their properties by 99 percent within the next 10 years.
O’Brien sees the bio-digester as a potential solution for horse ranchers, as well as environmentalists. According to the feasibility study, the city could create another waste barrel for residents, in addition to the trash and recycling cans already offered. Horse ranchers could put their manure in the barrel and a waste management company, such as E.J. Harrison & Sons, could pick up it up and transport it to the bio-digester, O’Brien said.
Other feasibility issues, such as how much a bio-digester might cost and where it might be located, are still being analyzed. According to preliminary estimates, the waste facility would be built on two to three acres, ideally located near another local waste or water treatment facility and roads.
“It needs to have proper industrial zoning, and there needs to be a place to use the energy nearby,” O’Brien said.
The bio-digester would cost between $6 million and $8 million to build, but would pay for itself in five to seven years, according to W2E’s preliminary estimates. The facility would generate income from the payments made by horse ranchers for barrel pickup and from selling the energy generated to another facility, such as a city wastewater treatment plant, enabling it to rely less heavily on the grid, O’Brien said.
“This is not new technology, there’s a bio-digester at Gills Onions in Oxnard, for example, but this application is pretty new,” he said. “Using horse manure is a pretty special, new thing.”
O’Brien hopes an oil or natural gas company seeking an alternative energy project in its portfolio may fund the construction. It will be at least two years before any building begins, he said.
Consultants from the infrastructure firm, AECOM, are conducting the feasibility study, funded through a $75,000 state grant and $25,000 from the county and fundraising. If, when completed in December, the study suggests that the project will be possible, W2E will try to secure grants for construction and further research.
“Even if this project doesn’t end up being feasible, at least we’ll have shed light on taking waste and making energy, and maybe something else will come out of it,” O’Brien said.