The intermittency of mainstream renewable sources is one of the biggest problems facing the energy industry. Solar power relies on the weather being sunny and without clouds, whilst wind power is only generated when the wind is strong enough to turn the wind turbines. The challenge is that supply and demand are not aligned, and energy storage options are required which enable the introduction of additional renewable energy. Currently around 20-30% of renewable energy is wasted since the power grid can´t balance the production and demand.
Long-term and large-scale energy storage options to utilise this excess or otherwise wasted energy from renewable sources, are required. Power to gas technologies provide such solution through the electrolysis of water into hydrogen and then the conversion of carbon dioxide into grid-quality renewable methane. The renewable methane gas can be injected into the existing infrastructure of the natural gas pipeline for storage and distribution and such it can be utilized for heating, transport, industrial use or even be converted back into renewable electricity.
How It Works
Renewable energy is used to power an electrolyser to split water in hydrogen and oxygen. The hydrogen and C02 undergo a biocatalytic reaction in single celled microbes called archaea. The result of this reaction is the production of biomethane, which is injected into the gas grid.
This process of biomethane production has several upsides compared to conventional thermochemical methanation processes:
- It can utilize mixed CO2 gas sources, such as raw biogas
- It provides high operational flexibility to follow wind or solar profiles
- The operating conditions are mild (65oC, 10barg) leading to low CAPEX and OPEX.
The reaction is also a form of decarbonisation, helping to remove carbon dioxide that would otherwise be released into the atmosphere and contribute to global warming.
And finally, the generation of low carbon renewable gas at scale, will be the solution to replace fossil gas with fully renewable gas as part of the energy transition.
Level 1 : Proof of Concept or lab test
Level 2: Tested under real life conditions
Level 3: Commercial solution