Despite concerns over Bitcoin mining’s energy consumption, Bitcoin mining has the potential to be a net positive for humanity’s relationship with energy and sustainability. This can be achieved by the mining industry using intermittent, stranded and waste power sources and subsidizing sustainable energy. A less-explored opportunity is to collect and redirect the excess heat generated by Bitcoin mining for other heating needs. This Earth Day, let us consider how Bitcoin mining can not only help our planet and improve humanity’s relationship with energy by serving as a buyer of zero-carbon energy, but it can also serve as a producer of recyclable and reusable energy.

Bitcoin’s energy recycling potential

Many of Bitcoin’s critics are understandably worried about Bitcoin’s rising energy consumption. The Cambridge Bitcoin Electricity Consumption Index indicates that Bitcoin’s electricity consumption has only ever gone up since the digital asset’s inception. Similarly, Bitcoin’s greenhouse gas emissions — although there have been ups and downs — have also grown over time.

But Bitcoin’s energy consumption is not the whole story. 

Bitcoin mining produces a lot of heat, and harnessing and redirecting that excess heat is not just a theoretical possibility. In fact, there are already plans for a Canadian city to be heated by Bitcoin miners. An energy provider, Lonsdale Energy Corporation, and MintGreen, a Bitcoin mining company, are partnering up to provide at least some of the heat demanded by the residents of North Vancouver.

MintGreen will recycle about 20,000 tons of toxic gas per megawatt that would have otherwise entered the atmosphere and contributed to global warming. Instead, this liability of toxic emissions will be turned into an asset: Over 95% of the energy that the miners initially consume will be converted into thermal energy that will be used to heat several buildings. Since Bitcoin miners can run continuously, and because there will almost certainly always be a supply of Bitcoin miners available, the city will be able to rely on their excess heat during any month of any year. 

This endeavor is not a pie-in-the-sky dream. MintGreen had already made deals with the Vancouver Island Sea Salt facility and Shelter Point Distillery to sell them heat during frigid Canadian winters.

Bitcoin mining’s versatility also allows its excess heat to be used for recreational ends. For example, it costs between US$2,000 and US$5,000 to heat a typical swimming pool. Bitcoin mining can turn this money sink and associated energy consumption into a zero-cost endeavor. All you have to do is connect your Bitcoin mining machine to your pool’s water pump. You simultaneously earn the hardest asset ever created and heat your pool at no additional charge.

While heating a swimming pool is an amusing application, Bitcoin miners’ excess heat has more profound use cases for humanity. Companies are already collaborating with researchers to create greenhouses that are heated by Bitcoin mining.

In the Netherlands, the heat from Bitcoin mining is warming a greenhouse for tulips and cutting the flower farmers’ reliance on gas, which has become more expensive since Russia’s war on Ukraine. In Sweden, another mining company’s 600-kilowatt ASIC machines’ heat is directed toward warming a 300-square-meter greenhouse in which fruit and vegetables are grown. The miners are embedded in a data center container, which is fitted with an air duct apparatus that draws heat from the ASICs and sends it to the greenhouse. In theory, this would keep the greenhouse at 77 degrees Fahrenheit continuously. Considering that the temperature of the area drops to minus 22 degrees Fahrenheit in wintertime, the potential savings on heat costs and use are significant. 

Just as Bitcoin mining can make good use of intermittent, stranded and waste energy sources, recycling and reusing miners’ waste heat can potentially increase the profitability and sustainability of indoor farming and food production. As one researcher said, “A 1 [megawatt] data center would have the ability to strengthen the local self-sufficiency up to 8% with products that are competitive on the market.”

Simmering tensions

Not everyone is excited about Bitcoin miners’ heat, especially those who suffer from its unintended consequences. For example, residents near Seneca Lake in upstate New York have complained that a nearby power plant’s collaboration with over 8,000 miners has caused their lake to “feel like you’re in a hot tub.”

The power plant takes in 139 million gallons of water from the lake and gives back 135 million gallons every day. The water that is recycled back into the lake gets up to 108 degrees Fahrenheit in the summer. To be sure, solutions can in principle be found, but we must nevertheless admit that sometimes miners’ heat can affect a community’s environment in ways that people do not enjoy.

Sustainable energy sources still matter  

Aside from Bitcoin mining helping subsidize renewable energy, our ability to harness and direct its excess heat is yet another way that Bitcoin can help combat climate change. Less than a decade ago, Imperial College London estimated that heating residential and commercial buildings accounted for almost half of all energy consumption and 40% of all energy-related carbon dioxide emissions. If all of this heat could be provided by carbon-neutral sources, it could be the most revolutionary impact on climate change in a generation.

On the face of it, replacing carbon-emitting heat sources with the excess heat of Bitcoin miners may not make enough of a difference. After all, if Bitcoin miners are themselves fueled by carbon-intensive fuel sources, then heating one’s home with miners’ excess heat does not necessarily reduce enough emissions for us to meet our climate goals.

But Bitcoin miners are unique in their ability to render viable renewable energy sources that would have not been profitable in the miners’ absence. Heating commercial and residential buildings with miners’ excess heat really could help put a dent in humanity’s carbon emissions — provided that the miners themselves are powered by, say, solar energy.

We have already seen that heating buildings and powering indoor farms with Bitcoin miners’ excess heat is not a pipe dream but a reality. It may not be a big leap to imagine what a difference it could make on our planet if Bitcoin miners could themselves be fueled entirely by carbon-neutral sources.