Driving the Future

HYDROGEN FUELS NET-ZERO MOBILITY

Mark Griffin, Hydrogen Market Development Manager for Clean Fuels, BOC, explains how using hydrogen as a transport fuel benefits councils and fleet operators. T he government’s ‘Road to Zero Strategy’ is driving the transition to zero emissions across all vehicle types for public and private modes of transport. The end of the diesel vehicle is in sight and forwardlooking councils and fleet operators are taking action to provide clean transport alternatives, from delivery vans to refuse trucks and bus fleets.

Zero-emission vehicles produce no greenhouse gas or air pollutant site from an offsite production plant or emissions at their tail pipes. Currently, only produced onsite. To produce hydrogen hydrogen fuel cell and pure battery electric on-site, an electrolyser is required vehicles can deliver zero emission transport. to extract hydrogen from water. A Both battery and fuel-cell vehicles use compressor unit takes the extracted electricity to drive electric motors, and both hydrogen and compresses it for efficient electricity and hydrogen can be produced storage. The station also requires a using power from renewable energy sources. hydrogen store, which is capable of HYDROGEN AS A FUEL storing hydrogen under pressure, and a dispenser for pumping the hydrogen

Hydrogen is the most abundant element gas to the vehicle under pressure. in the universe. It is produced in a number of For any refuelling station, ensuring ways, which vary in efficiency, carbon intensity reliability is essential. At BOC’s and cost including as a by-product from the Kittybrewster facility in Aberdeen, every chemicals industry or through a process refuelling has been successful since the called steam methane reformation (SMR). It station’s launch in 2015, and the reliability is also possible to produce green hydrogen rate is 99.5% with no failed refuels. from electrolysis – a process that extracts Also important is the need to ensure hydrogen from water with no emissions. that the refuelling capacity is large

Hydrogen is stored as a compressed enough to supply the vehicle fleet for gas at the refuelling station until it’s needed which it is intended. Producing 300kg and is then pumped into a vehicle under of hydrogen daily is enough to fuel ten pressure. One of the key benefits of hydrogen 42-seat buses, with each bus able to is that refuelling is a fast and familiar process, travel up to 350km between refuelling. similar to refuelling a diesel vehicle. It takes By using a modular design, it is possible around 10 minutes to refuel a bus, which to scale up hydrogen production to can cover a range of around 350km, and 5 match the needs of a growing fleet. minutes for a car enabling a range of 500km.

There are zero emissions from the COST OF OWNERSHIP fuel-cell vehicle – just clean water from the There are several factors that tail pipe – and they are virtually noiseless. contribute to the cost of operating REFUELLING STATION INFRASTRUCTURE a hydrogen refuelling station. Two of the main determinants are the volume of hydrogen produced (cost

Refuelling stations need a hydrogen reduces with increasing volumes) supply, which can either be delivered to and the cost of electricity used in the electrolysis process. For a low-carbon solution, operators typically source power from renewable sources or a supplier offering a green tariff.

Some operators aim to achieve cost parity with diesel at the pump, while others recognise that there is a significant value associated with reducing air pollution and carbon emissions. Producing hydrogen using methods other than electrolysis does create some CO2 emissions. It can, however, be cheaper, improve local air quality and provide a pathway to using green hydrogen in the future. With any new project, BOC works with local councils and vehicle fleet owner/operators at the outset to help them understand the economics of hydrogen use, align the costs with their objectives and identify potential sources of funding.

Element Energy, a specialist low carbon energy consultancy, reports that by the mid-2020s bus manufacturers expect it will be possible to purchase a fuel cell bus for less than £350k. This

cost assumes relatively low production volumes – a few hundred per year. With expansion in the global supply of the key components of fuel cell systems and hydrogen tanks, it is reasonable to expect prices to reduce to below £300k by the end of the decade.

At these bus prices, the total cost of ownership of a fuel cell can fall below even the best case battery electric options (when coupled with the price of hydrogen that will be available at high-volume refuelling stations). Element Energy concludes that, as cities regulate to require zero emission buses during the 2020s, the fuel cell bus has the potential to be a major part of achieving this political ambition. RENEWABLE ENERGY AND GRID BALANCING

With more renewables on the grid, energy supplies are becoming more intermittent, and real-time electricity prices more volatile.

When supply exceeds demand, first open access hydrogen refuelling energy becomes very cheap – station in Swindon, UK, in 2011. In sometimes negatively priced, as the 2014 the site was further developed alternative is that operators must be to become the first commercial scale paid to curtail generation. Building production and refuelling station with energy storage facilities helps to the installation of an onsite electrolysis balance the grid by storing energy unit producing green hydrogen powered when it exceeds demand, then using by solar. Since then, BOC has been it when demand picks up again. working with partners to develop a

Using electrolysis, hydrogen can act public UK hydrogen refuelling network, as a very cost-effective energy store and including the first UK hydrogen station so help balance the grid. The flexibility of on a public fuel forecourt at Shell’s the proton exchange membrane (PEM) Cobham service station on the M25. technology used within the electrolyser BOC’s relationship with Aberdeen enables the electrolysis process to be City Council to develop, construct and switched on and off very quickly to operate the Kittybrewster refuelling respond to electricity price volatility station, is a major success. Together, and take advantage of low electricity they are creating a blueprint for rolling prices. Hydrogen provides a way to store out hydrogen technology across electricity when it is cheap, which can towns and cities in the UK, helping reduce the cost of hydrogen at the pump. to reduce carbon emissions and air ESTABLISHED, PROVEN TECHNOLOGY pollution, which is a major benefit for all. www.boconline.co.uk

Hydrogen refuelling is in daily operation worldwide. BOC launched the ENERGY MANAGER MAGAZINE • JUNE 2020