Two years ago, former SpaceX engineers used rocket technology to develop a power plant that could remove carbon dioxide from the atmosphere (with a small asterisk). Burning plant waste to emit CO2, it became a kind of “vegetarian rocket engine” for the power grid.
This week, Arbor Energy announced that it has raised $55 million in Series A led by Lowercarbon Capital and Voyager Ventures, following a partial pivot. The power plant would be more omnivorous, capable of burning natural gas in addition to biomass, rather than adhering to a strict vegetarian diet.
The change came this year as demand for electricity from data centers soared. Existing designs were fully capable of powering AI servers, but their range was limited by their wood and agricultural waste sources. Natural gas is more widely available.
Arbor still plans to capture CO2 from power plants that use oxyfuel combustion, which converts hydrocarbons into syngas and burns them in the presence of pure oxygen. The result is CO2 that requires less preparation for sequestration.
Arbor spokesperson Patrick Mahoney told TechCrunch that, thanks to tax credits, storing CO2 is cheaper than releasing pollutants into the atmosphere. The company does not intend to sell its technology to companies that do not plan to capture and use or sequester carbon, he said.
But waste CO2 isn’t the only climate change consideration when it comes to burning natural gas. The main component of natural gas is methane, a powerful greenhouse gas that causes 84 times more global warming than carbon dioxide over 20 years.
As such, leaks in the natural gas supply chain can have a significant impact on the climate impact of natural gas-fired power plants. A low leakage rate of 0.2% means that gas-fired power plants can have the same carbon footprint as coal-fired power plants, according to a recent study. The U.S. government estimates the leak rate across the oil and gas supply chain to be approximately 1%, but satellite measurements show the leak rate to be approximately 1.6% across the United States.
Arbor said it works with natural gas suppliers that have been certified to have low leakage rates, with the goal of ensuring that each kilowatt of electricity generated has less than 100 grams (about a quarter pound) of climate impact.
The startup confirmed it is building a biomass-burning power plant in Louisiana. The factory is partially funded by a $41 million deal with Frontier, a developed markets effort backed by Stripe, Google and others. Under the agreement, Arbor will be required to remove 116,000 tonnes of carbon dioxide by 2030.
