Engineering news
Gas supplier BOC has opened the UK's first “green” commercial-scale hydrogen refuelling station at the Honda factory in Swindon to test the commercial viability of the technology.
The refuelling station at Swindon uses electricity from a nearby 15MW capacity solar photovoltaic plant to power an industrial electrolyser, which produces hydrogen from water to be dispensed for several applications.
The hydrogen leaves the electrolyser, which was manufactured by Belgian company Hydrogenics and consumes around 4,9 kWh/Nm3 of electricity, at 9bar. The hydrogen is then compressed in a single stage up to 900bar and stored for use in several applications: a dual pressure refuelling pump for cars that use hydrogen at 700bar and commercial vehicles at 350bar; a forklift refuelling station within the honda factory operating at 350bar, and a small building which uses a M-Field fuel cell system operating at around 5bar to supply heat and light.
The hydrogen station can produce and dispense 3kg of hydrogen an hour, up to 200kg a day, and store up to 135kg. When the pressure drops in the hydrogen store, the system responds by producing more hydrogen to repressurise and “top-up” the storage. The hydrogen production and storage process takes around 90 minutes from start to finish.
Nick Rolf, innovation manager at BOC, said: “The system is designed to operate on pressure. We are trying to design the system to sync with the demands of the customer. That will help us understand total cost of ownership and the performance and efficiencies of these transitional technologies and vehicles.
“We want to know the lowest cost and what the price of hydrogen will be at the pump. We've got an idea of what it will be, but this will validate that and stress test the concept. If it doesn't stack up commercially no one will want to buy the next one.”
The most energy intensive stage of the hydrogen production and storage process is the compression, the power for which all comes from the solar PV. However, the facility is also connected to the grid and has backup storage of bottled hydrogen to ensure a constant supply to customers.
The 3kW fuel cell in the adjacent building, which is being used as a hydrogen “education centre”, was installed by Fuel Cell Systems. The building uses 1kW of electricity to run without heating and also uses warm air produced by the fuel cell for heating. Karen Sperrey, operations director at Fuel Cell Systems, said: “Using a PEM [Proton Exchange Membrane] fuel cell to provide both power and heat is a notable first in this power range.”
The Honda Swindon station, which has been part-funded by InnovateUK, was the first hydrogen station open to the public in the UK when it opened in 2011 and previously ran off bottled hydrogen delivered by BOC. The station's expansion comes after business minister Matthew Hancock last week announced £11 million of government and industry funding to establish a network of 15 hydrogen refuelling stations across the country by 2015 and encourage the uptake of hydrogen-fuelled vehicles. This week retailer Sainsburys announce it would trial a hydrogen fuel pump at a supermarket in Hendon, north west London as part of the £11 million program.
Kate Warren, from the government's Office for Low Emission Vehicles, said: “The move to ultra low emission vehicles is a once in a lifetime opportunity. Up until the government has been focussed on battery electric vehicles, but it is technology neutral and doesn't want to pick winners. We're trying to overcome the chicken and egg scenario with the infrastructure and vehicles.”