Dairy by Tomales Bay finds way for its cows to fuel truck that brings them feed.
With barely a sound, the red and white International Harvester feed truck unloaded a mix of silage, barley and rice to a dozen pregnant cows, releasing a sour, grassy aroma into the foggy morning at Straus Family Creamery in Marshall. The all-electric feed truck is entirely powered by methane gas that was released by the farm’s 280 cows, or rather, their poop.
“I like to say the cows are powering the truck that feeds them,” said owner Albert Straus, whose organic dairy is perched on the edge of Tomales Bay in Marin County.
The truck, which went into service this month, had a timely debut. On Tuesday, Gov. Jerry Brown signed legislation extending cap-and-trade regulations, AB398, part of the state’s effort to cut greenhouse gases 40 percent below 1990 levels by 2030. Methane gas heats up the atmosphere as much as 20 times as quickly as carbon dioxide, and a big source is cow manure and burps.
“What we’re trying to make here is a model of showing that farms can be part of the solution for climate change.” Albert Straus, owner, Straus Family Creamery
All of the electricity needed to run the Straus truck, several smaller vehicles and the entire dairy farm comes from a system fueled by methane gas from the cows’ manure. (The gas in bovine belches is harder to capture.) The truck serves only one of nine dairies that produce milk for Straus Family Creamery, so it’s just a start. But Straus, whose farm has been off the grid since he installed the methane-powered energy system in 2004, hopes it can be an example to other dairies in California, and, he said, the world.
“What we’re trying to make here is a model of showing that farms can be part of the solution for climate change,” said Straus, whose farm has a 20-year plan to sequester the equivalent of 2,000 metric tons of carbon dioxide per year. The United Nations estimates that livestock are responsible for 14.5 percent of the planet’s greenhouse gas emissions.
Around 20 California dairies have methane digesters, including Straus’ neighbor Giacomini Ranch, but most are in the Central Valley. Hilarides Dairy in Lindsay (Tulare County), which has two, converts methane to compressed natural gas instead of electricity to run milk trucks and other vehicles.
Here’s how the digester works at Straus: Workers clean out the dairy barns every night and flush the manure through a separator. Solids get dried as fertilizer for the nearby pasture where the cows graze, and liquids fill two lagoons. One is covered by a tarp that traps methane gas, which gets funneled into a combustion engine that fuels a generator. The system makes enough energy to run the farm, its smaller electric vehicles and now the truck. Plus, heat generated by the engine in turn warms the water used to clean the barn.
“The electric truck is closing the loop,” said Straus, who spent about $130,000 to convert the truck. A new diesel truck costs $65,000 to $100,000. However, he estimates that the truck will save the farm $10,000 a year in fuel and maintenance.
Methane digesters cost quite a bit more, at an estimated $1,000 per cow; Straus spent more than $300,000 when he first put one in. Some grants are available, but the funding is still not enough to make it affordable. Straus said he’s been in talks with state lawmakers to create loans for farmers. He has also consulted with a company in Washington state that could potentially build and maintain methane digesters for dairies, so that dairy farmers can focus on their livestock.
Straus worked with a local mechanic to convert the farm’s 33,000pound feed truck to electric. Unlike electric cars, there’s no range anxiety: The truck doesn’t need to go long distances because workers can plug it in between feed loads.
While large electric trucks are relatively new to farms, electric delivery trucks are used by companies like Coca-Cola, and Tesla Motors announced that it would debut an electric semi this fall.