Climate + Farm

Innovating for Tomorrow

Renewable energy is one of the focuses of the Straus Dairy Farm’s sustainable model. At the dairy farm, the methane digester captures methane (a greenhouse gas) from the cows’ manure and transforms it into electricity. Operating since 2004, the methane digester provides enough renewable energy to power the entire dairy farm, charge Albert Straus’ electric car and other farm vehicles.

Poop to Power — Cow Methane Fuels the Straus Dairy Farm

The digester has significantly reduced methane emissions by more than 1,600 metric tons of CO2e each year — equivalent to eliminating the annual greenhouse gas emissions from about 350 passenger cars. To put that into perspective, if two-thirds of California dairies added methane digesters to their manure management practices, the reduction in emissions would be the equivalent of taking about one million passenger vehicles off the road, according to Straus Family Creamery’s calculations.

It all adds up to a common sense approach to our future energy needs. Dairy farmers in California are already facing pressure to lower methane emissions under the state’s ambitious new greenhouse gas reduction laws, which include methane emission reduction targets of 40% below 2013 levels by 2030. The state’s Air Resources Board suggests much of that reduction should come from converting methane from cow manure into energy.

 

The digester has significantly reduced methane emissions by over 1,600 metric tons of CO2e each year – equivalent to eliminating the annual greenhouse gas emissions from about 350 passenger cars.

Sustainable Organic Farming and the Fight to Reverse Climate Change

In summer of 2017, Albert Straus introduced the first full-scale electric truck – powered by cow poop. This truck is the next step in Straus’ quest to show that his organic dairy farm can be carbon positive, using agriculture as a solution for reversing climate change.

Straus and a local mechanic spent eight years developing an environmentally-friendly alternative to diesel-fueled trucks: The feed truck’s motor is charged from electrical power generated from methane gas produced by the cows’ own manure.

“What I’ve tried to do is create a sustainable organic farming model that is good for the earth, the soil, the animals, and the people working on these farms, and helps revitalize rural communities.” Albert Straus

How the Methane Digester Works

Twice a day the barns are flushed clean with recycled water, including water that has been recycled from the Creamery. Manure from the barn is also scraped by tractor into a holding pond. From there, the manure goes through a separator, which splits solids from liquids. The solids are then composted while the liquids are piped into a second pond covered with an enormous tarp. Under the tarp, the liquid manure is transformed by bacteria through the process of anaerobic digestion. The result of this sustainable practice is renewable energy in the form of methane gas, carbon dioxide, and a small amount of hydrogen sulfite.

The tarp captures the gas, which is pumped to a combustion engine where it fuels a generator and creates electricity. The heat created in the process provides 180° F water that is used to clean barns on the dairy farm.

Sustainable Benefits

There are many benefits to this system beyond the energy it generates. The most important is preventing methane gas, a greenhouse gas but a short-term pollutant that is 72 times more detrimental than carbon dioxide within a 20-year period, from entering the atmosphere. The system also greatly eliminates odors on the farm and significantly reduces flies. In addition, two byproducts — separated solids and leftover liquids — are used as organic fertilizer on pastures. Plus, the system allows the Straus Dairy Farm to run electrical meters in reverse and to offset electrical usage from other meters at the farm.

The Sustainable Facts:

  • Generator capacity: 80 kW
  • Average performance per month: 28,800 kWh
  • Average performance per day: 960 kWh
  • Implementation cost: $334,680 — initial conversion to anaerobic digester plus refurbishment
  • Initial funding: $155,261 — DPPP and EPA through CA Water Quality Board
  • Annual cost savings: $40,000 – $50,000
  • Return on investment: 4-5 years

 

“My electric feed truck is not only a practical tool for my organic farm. It is also a symbol of the resourcefulness we need to fight climate change, which threatens our business and the future of American farming.” Albert Straus

Carbon Farming is Agriculture’s Answer to Climate Change

Climate change is a universal global issue. The regenerative agricultural practice of carbon farming on organic dairy farms is helping move carbon from the atmosphere and put it back into the soil. The environmental benefits include:

  • Promoting soil health through rotational grazing: Cows are moved to different pastures every few days which improves pasture productivity, stimulates plant growth, allows the pastures time to regrow and produce more nourishing grasses.
  • Building nutrient-rich soil: Applying compost on managed pastures improves soil organic matter, enabling more water retention in the soil and the farm’s ability to sequester carbon. Higher organic matter, better nutrition, and rotational grazing practices allow for healthier plants and more vegetative biodiversity.
  • Restoring woodlands and streams: Through photosynthesis, trees and streamside plants protect riparian habitat and pull carbon from the atmosphere back into the soil creating cleaner waterways and root systems, which reduces erosion during floods.
  • Reversing climate change: Implementing sustainable organic farming practices such as carbon farming helps reduce global warming emissions.

In 2013, the Straus Dairy Farm became the first dairy farm in California to implement a carbon farm plan, in conjunction with the Marin Carbon Project, a 20-year carbon farm plan that will reduce and sequester 2000 metric tons of CO2e every year. A large portion of the carbon farm plan (about 80% or 1650 metric tons of CO2e) is mitigated through methane destruction from the methane digester.

Around 320 metric tons of CO2e is sequestered from the atmosphere back into the soil each year through carbon farming practices. This is done by adding compost on pasture to increase soil health, planting wind breaks and hedge rows to reduce soil erosion, planned rotational grazing of animals to best manage pasture health, and planting perennial grasses to increase underground root systems.

In addition to combating global warming, carbon farming practices also work to improve the health of farm soils. When soils are healthier, they naturally increase the volume of pasture production; and with increased pasture production, cows have more nutritional-rich grasses and farmers can reduce outside feed costs.

Straus Family Creamery educates the importance of carbon farming and inspires its implementation to the certified organic dairies supplying milk to the Creamery, and other dairy farmers throughout the state and rest of the country. The hope is that other farmers will learn and adopt these sustainable practices — responsible approaches that offer feasible solutions and positively benefit the environment.

In the “greenhouse gas offset” industry, carbon farming is now a codified methodology for creating carbon offsets from rangeland composting (a primary practice of carbon farming). The American Climate Registry (ACR) developed the protocol “Compost Additions to Grazed Grasslands” allowing farmers to trade their carbon offsets on a voluntary carbon market through ACR. This means that farmers or ranchers are now potentially able to get paid for carbon farming through the sale of offsets — a significant step forward.

Adopting these practices can bring huge benefits. For example, if farmers spread a quarter inch of compost on just 50% of California’s rangelands, 42 million metric tons of CO2e would be offset, equivalent to all the energy use for commercial and residential sectors in California. (Source: Marin Carbon Project, 2013)

The San Francisco Chronicle reports that if compost were applied over 5% of the state’s grazing lands, the soil could capture a year’s worth of greenhouse gas emissions from California’s farm and forestry industries, or the equivalent of removing 6 million cars from the road.

A carbon farm plan helps farms be more sustainable financially and be part of the bigger picture. Organic dairy operations are an important solution to climate change. Farmers can use methane to create renewable energy and use animals to help sequester carbon.