Hydrogen Fuel Cell Bus Technology State of the ... - NEXTHYLIGHTS
Hydrogen Fuel Cell Bus Technology State of the ... - NEXTHYLIGHTS
Hydrogen Fuel Cell Bus Technology State of the ... - NEXTHYLIGHTS
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<strong>Hydrogen</strong> <strong>Fuel</strong> <strong>Cell</strong> <strong>Bus</strong> <strong>Technology</strong> <strong>State</strong> <strong>of</strong> <strong>the</strong> Art Review<br />
Hybrid fuel cell bus trials, by contrast, have shown relatively poor availability (55-<br />
80%) in trials before 2010. These will need to be improved before <strong>the</strong> technology<br />
can be rolled out outside small demonstration trials. The next generation <strong>of</strong> hybrid<br />
fuel cell bus trials (starting 2010) are designed to prove that <strong>the</strong> technology can<br />
achieve availability standards over 90% which will be sufficient to begin to<br />
commercialise <strong>the</strong> technology.<br />
The next generation <strong>of</strong> bus demonstrations (such as CHIC 20 ) are also aimed at<br />
understanding <strong>the</strong> fuel economy <strong>of</strong> next generation FC buses. Initial tests suggest<br />
<strong>the</strong>y will achieve <strong>the</strong> lower bound <strong>of</strong> <strong>the</strong> fuel consumption range, e.g. up to 40%<br />
improvement over an equivalent diesel route at parity <strong>of</strong> calorific content.<br />
The main technical constraints for fuel cell buses, compared to conventional diesel<br />
vehicles are:<br />
o Fill time – which is currently around 10 minutes (best available is 7 minutes),<br />
compared to a diesel fill times <strong>of</strong> approx. 3 minutes. This creates logistical<br />
problem for bus operators.<br />
o Availability – equivalent availability to diesel vehicles has not yet been<br />
demonstrated for fuel cells in hybrid configurations. This is expected to be<br />
achieved in <strong>the</strong> next generation demonstrations.<br />
o Lack <strong>of</strong> infrastructure – meaning that dedicated hydrogen fuelling<br />
infrastructure is required at hydrogen bus depots – this is bulky and also<br />
requires very high availability as <strong>the</strong>re are no local back-up options available<br />
Diesel hybrid vehicles are currently gaining traction in <strong>the</strong> market for environmentally<br />
benign urban buses. These have a total cost <strong>of</strong> ownership higher than diesel buses,<br />
suggesting public authorities are prepared to fund some additional cost <strong>of</strong> operating<br />
environmentally friendly<br />
However, a Total Cost <strong>of</strong> Ownership analysis for today‟s fuel cell buses suggests<br />
that <strong>the</strong> cost <strong>of</strong> operating a fuel cell bus today is over three times that <strong>of</strong> a<br />
conventional diesel bus. This additional cost is not acceptable to bus operators,<br />
meaning <strong>the</strong> technology must reduce in cost to gain genuine commercial traction.<br />
There are two main approaches to cost reduction. In <strong>the</strong> first, progressive<br />
generations <strong>of</strong> fuel cell systems designed for buses are projected to reduce fuel cell<br />
system costs below €2,000/kW (from over €4,000/kW today), whilst increased<br />
volumes <strong>of</strong> fuel cell buses reduce <strong>the</strong> costs for bus builders to assemble and sell <strong>the</strong><br />
buses. This would reduce fuel cell bus costs to a lower bound <strong>of</strong> approximately<br />
20 http://chic-project.eu/<br />
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