Methane makeover: How a Cambridge company is turning pollution into progress

Climate change driven by the greenhouse effect is one of the primary challenges facing our species, and it’s vital to explore every possible avenue for slowing its progress. New technologies for carbon capture and sustainable energy production have a key role to play in this.

Discussions about greenhouse gases usually centre around CO2, which is indeed the predominant driver of anthropogenic climate change. However, it isn’t the only major culprit: according to the International Energy Agency, methane (CH4) in the atmosphere is responsible for 30% of the rise in global temperatures since the industrial revolution, with the rest mainly being CO2.

There are several major sources of human-produced methane, and in many cases it’s incidental (as with agricultural emissions) or unintentional (incomplete combustion of biofuels, decomposition in landfills). It’s important to find sustainable ways to dispose of this unwanted methane that don’t involve releasing it into the atmosphere to contribute to the greenhouse effect.

The most obvious way to get rid of methane is to burn it, and indeed it’s routinely burned as the primary component of natural gas. Unfortunately, burning methane just produces CO2, so it isn’t an appropriate means of disposal from an environmental perspective. To handle waste methane sustainably, we need to dispose of it without burning it.

It’s in this context that I’d like to highlight Levidian, which is a Cambridge-based company founded in 2012 specialising in disposing of methane in a way that isn’t just clean, but also provides desirable products from unwanted waste gas.

Levidian’s carbon capture system is called LOOP. It works by using microwaves to ionise methane gas, splitting the CH4 into its composite C and H in a high-temperature plasma. This plasma can be processed to produce elemental hydrogen as a gas, and elemental carbon in the form of graphene. Other hydrocarbons are produced as well, and these can be processed by LOOP again to convert a higher proportion into hydrogen and graphene.

This process, of course, requires energy input to power the microwave source and run the processing facility – it’s important for that electricity to come from renewable sources, since using fossil fuel energy would defeat the goal of sustainability.

A key benefit of this approach is that both hydrogen gas and graphene are valuable in themselves, and can be difficult to manufacture sustainably or in large quantities. Hydrogen gas (H2) is a clean energy source that can be burned to produce only water, and indeed some hope that one day we’ll transition to a largely hydrogen-based energy economy. The realisation of graphene was awarded the 2010 Physics Nobel Prize, and it’s attracted a lot of interest since then for its potential technology applications (as a flexible conductive material with a very distinctive electronic structure).

Levidian’s LOOP technology has very exciting potential. Waste methane will keep being produced for the foreseeable future, but perhaps it could be harnessed so that, rather than a harmful greenhouse gas, it serves as a sustainable, large-scale source of hydrogen gas and graphene.