Spotlight on: Turbines and Renewable Gases!
28 March 2019
The future European energy mix will no longer rely on fossil fuels. EUTurbines puts the spotlight on renewable gases such as biomethane, synthetic methane or hydrogen as solution to fully decarbonise dispatchable power generation. The document highlights the necessity of gas turbine technology and power-to-gas installations to arrive to a complete decarbonisation of the European energy system.
Europe goes carbon-neutral!
With its 2050 Long-term Strategy, the Commission is calling for a carbon-neutral economy by 2050. The vision is in line with the Paris Agreement objective to keep the global temperature increase below 2°C and pursue efforts to limit it to 1.5°C.
For the future European energy mix, this implies that it can no longer rely on fossil fuels. This fundamental transition is heralded by the coal phase-out in most European countries and, in some countries, accompanied by the additional decision of stopping nuclear power generation as well. Consequently, the question of stability of supply arises.
Policy makers and experts already acknowledged that a realistic discourse around the complete decarbonisation of the European energy system needs to go far beyond the technically and economically unfeasible concept of full electrification and will require contributions from all energy carriers, including gas.
To arrive to complete decarbonisation of the future European energy mix, also the decarbonisation of the entire gas infrastructure and the transition to a renewable gas grid needs to be accelerated. ‘Renewable gas’ is a broad term that usually refers to renewable hydrogen, biogas, biomethane or synthetic methane that shall gradually replace natural gas.
1. Renewable Hydrogen:
Renewable or green hydrogen is generated by water electrolysis using excess power generated from variable renewable sources. Electrolysis splits water (H2O) into oxygen, released into the atmosphere, and hydrogen. The hydrogen, obtained from this power-to-gas process, is a renewable gas that, – while it behaves differently than natural gas – can be used in gas turbines and processed with zero CO2 emissions.
2. Synthetic Methane:
Synthetic methane is generated by adding CO2 to hydrogen, in a process called methanation. The big advantage: Synthetic methane has the same performance behaviour as natural gas. It can easily be injected directly into the gas grid and handled by existing gas power plants without major modifications. The disadvantage: the additional methanation process reduces the overall efficiency.
If the CO2 added to the renewable hydrogen is captured from the ambient air, the synthetic methane is absolutely carbon-neutral.
3. Biogas and Biomethane
Biomethane is” cleaned” biogas, which is obtained from organic waste material, such as animal waste, waste water, agricultural crop residuals, manure, green and food waste or landfills. This chemical decomposition process is called anaerobic digestion. The biogas is then conditioned and filtered. This purification process upgrades the Biogas to Biomethane.
Biomethane can be used interchangeably with natural gas as it has pipeline-quality, meaning that it can be directly introduced into the existing gas grid and combusted in a gas turbine.
Power-to-Gas-to-Power: The future role of gas turbine technology
Variable renewable energy sources, such as wind or solar photovoltaics, are dependent on weather conditions. There will be more and more times, when the generated electricity will exceed demand and, on the opposite end, moments when there is not enough electricity from wind and sun to meet the demand.
Power-to-Gas technologies provide a solution for both situations by converting variable renewable energy into green storable fuel:
Excess power from wind and sun at times of low demand is not curtailed but converted via electrolysers into hydrogen. It can be stored and used in times of a shortage of supply by generating, carbon-free electricity with gas turbines. Therefore, the combination of green hydrogen and gas turbines offers dispatchable, reliable and efficient power and heat, independently of weather conditions to ensure the stability of a decarbonised European grid, using the existing gas infrastructure. By utilising renewable fuels, thermal power plants become dispatchable renewable energy technologies.
The green revolution of the gas turbine sector
To achieve a carbon-neutral economy by 2050 and to meet the objectives as set by the Paris agreement, decision makers need to adopt a technology neutral approach when selecting power generation technologies.
Showing its support to the decarbonisation of the EU energy system, the European gas turbine industry signed a set of commitments to drive the sustainable energy transition. Integrating the gas turbine sector into the green revolution is essential as it will allow for the utilisation of the existing infrastructure.
To share some highlights: EUTurbines members are dedicated to deliver technologies that can operate with high shares of renewable gases. Gas turbines can already operate with renewable gases generated from carbon-neutral sources such as biomethane or synthetic fuels, like synthetic methane. With regard to hydrogen, today turbines can operate with a mix of natural gas and 3-5% hydrogen, while ensuring safety and compliance with emission standards. Our industry is committed to provide gas turbines that can handle a share of 20% hydrogen by 2020 and gas turbines operating with 100% hydrogen by 2030.
How to make it happen?
The switch to renewable gas requires the support of policy makers addressing technical challenges via research and innovation funding, allowing the development of fast, efficient and sustainable innovative solutions towards a decarbonised European energy system.
It means investments in energy efficiency of power-to-gas conversion and power-to-gas-to-power installations, to fully exploit the benefits of long-term storage and dispatchable, decarbonised power and heat generation and recognise their value for Europe’s society and economy.