Is hydrogen the answer to low-emission turbomachinery?

Is hydrogen the answer to low-emission turbomachinery?

On June 29th, Turbomachinery International jointly hosted a webcast with ETN Global entitled “Is Hydrogen the Answer to Low-Emission Turbomachinery?”. It provided an overview of the various elements of the hydrogen economy, the different types of hydrogen (gray, blue, green), the turbomachinery challenges involved (the design of combustors, pipelines etc.), and the economics of hydrogen.

Three guest speakers were invited to speak, each an expert in their field.

Pierre Dechamps

Pierre Dechamps is an Ambassador at EU Climate Pact and a Senior Advisor at FTI Consulting. He remarked on the state of emissions in Europe, which spurred the creation of the EU’s “Green Deal”. This legislation aims to reduce CO2 emissions to zero by 2050.

Dechamps said changes to Europe’s power generation practices are essential in meeting this goal. Europe aims to transition towards a fully integrated energy system to reduce waste by storing and sharing energy.

In his opinion, hydrogen would be a key player in this new system. Excess energy from renewables would be used to generate hydrogen.

The EU’s “Hydrogen Strategy for Climate Neutral Europe” sets a schedule for at least 6 GW of renewable hydrogen electrolyzers to produce up to 1 million tonnes of renewable hydrogen by 2024; increasing to 40 GW between 2025 and 2030. Beyond 2030, the ambitious plan is to have renewable hydrogen fully integrated into the system, extending to hard-to-decarbonize sectors such as transport.

Geert Laagland

Geert Laagland, Director of Engineering at Vattenfall and Co-Chairman of ETN Global’s Hydrogen Working Group spoke on the role hydrogen could play in the heat and power sectors. He believes a flexible backup to intermittent renewables is necessary for Europe’s transition from fossil fuels and gas turbines powered by hydrogen would effectively fill this role.

According to Laagland, hydrogen gas plants are ideal for creating CO2-neutral, flexible dispatchable power. He believes that power generation using blue (and eventually, green) hydrogen can be realized by 2030. Hydrogen plants will also require fewer operating hours, making them more economically attractive compared to current natural gas plants.

Laagland also spoke on heat generation, using district heating in Berlin as an example. He detailed Vattenfall’s plans for transitioning this heating program from coal to low-carbon hydrogen by around 2040.

Laagland provided a graphic showing the development of a hydrogen-based infrastructure in Europe (see figure). Gas turbines and compressors will be required throughout the hydrogen ecosystem. He pointed out that it will be necessary for Europe to import hydrogen from other countries. He also mentioned the importance of storing hydrogen as the “the production and consumption of hydrogen will be out of sync.”

In conclusion, Laagland noted that for hydrogen to be implemented on a large scale, many regulatory and market conditions still have to be met. This includes pricing incentives for hydrogen, converting and building infrastructure, and a sufficient supply of renewable electricity.

Peter Stuttaford

Peter Stuttaford, CEO of Thomassen Energy/PSM drew attention to the renewable energy production gap. In his opinion, the gas turbine is poised to fill that gap in a variety of ways. He mentioned flexible fast-load coverage, the fact that natural gas is the cleanest fossil-fuel, and that turbines can run on a variety of fuels.

With certain upgrades, natural gas plants can slowly progress towards using 100% hydrogen. This will allow for a realistic transition away from fossil fuels while still adhering to net-zero goals.

Stuttaford detailed the retrofit process necessary to allow a gas turbine to run on hydrogen. The combustor must be replaced due to increased flame speed and the wider flammability limit of hydrogen. Next, the turbine must be evaluated for heat load due to the higher volumetric flow. Finally, the exhaust must be inspected to ensure an adequate margin.

Additionally, fuel delivery manifolds and fuels line may need to be resized, and controls systems and fuel delivery skids may need to be upgraded.

As an example, Stuttaford showed a site in The Netherlands where Thomassen Energy/PSM had upgraded a plant’s GE 9E turbines to run on up to 35% hydrogen by volume. For the past three years, the plant stably run on up to 25% hydrogen and maintained sub-9ppm NOx.

His company’s FlameSheet technology was described as “a combustor within a combustor” and is used to upgrade existing turbines. Stuttaford said it allows turbines to run on up to 60% hydrogen. It is also being tested when alternating between 100% natural gas and 100% hydrogen.

He advocated a ‘turnkey clean energy package’. It would include an electrolyzer, upgraded gas turbine, and a high-pressure storage vessel for hydrogen.