H2 fuel cells are the future of mobility
In a recent KPMG study, in which more than a 1000 leaders in the car manufacturing industry were asked about their vision for the future, over 80% of the respondents identified FCEV's (Fuel Cell Electric Vehicles) as the most likely solution for long-range mobility in the near future.
However, there are still some hurdles to take:
This results in a catch-22 situation that can only be broken by a joint effort of car manufacturers, hydrogen suppliers, suppliers of gas-handling infrastructure and governmental bodies. Howden is determined to take on this responsibility and has developed a range of compressors that fit the need for an affordable source of uncontaminated hydrogen at the high pressure needed for long range mobility.
Pressure of hydrogen inside a vehicle reaches 70 MPa during fuelling. Moreover, in order to achieve a quick charging cycle of around 3 minutes, the hydrogen needs to be compressed to maximum 100 MPa to ensure sufficient flow. This is a pressure level that is beyond most available standard compressor types.
Fuel cells are very sensitive to contamination of the hydrogen supplied to them. Impurities may result in irreversible damage to the membrane and the fuel cell as a whole. The compression system plays a large role in this, as it can be the primary source of contamination if the wrong solution is chosen. Therefore a diaphragm compressor is the most ideal compressor type because of the lack of lubrication and wearing parts in the compression chamber.
Reliability is a key factor. Since hydrogen fuelling stations are not around in abundance, down time of the components of the fuelling stations will without doubt lead to vehicles standing still for lack of fuel. End-users are depending on an interrupted fuel supply, and since this is a critical issue all suppliers have a responsibility to do the utmost to prevent this.
Since the technology is still developing, there is no standardised solution. For example, hydrogen can be supplied by tube trailer, made on site from natural gas in a SMR or made from wind or solar energy with an electrolyser.
All these different options put different demands on the compressor at the suction side. So customisation is a key feature.
Lead time is essential when a new fuelling station is planned. Once a concession is given, every day counts, with delay resulting in unexpected costs.
The compressor is, as the most specialized piece of equipment on-site, a major factor in the cost of a fuelling station. In order to minimise investment and financial risk, the cost must be reduced as much as possible.
A hydrogen refuelling station
Fuel cell powered forklift
Howden has used its 100+ years of experience in hydrogen compression to find a solution that addresses all points above.
Henri Corblin, one of the founders of Howden Burton Corblin (HBC), invented the diaphragm compressor in the early 20th century. Since then, it has remained the optimal solution for high pressure compression of gasses that need to be kept absolutely separated from their environment, and remain free of contamination.
A good example of this is the use of diaphragm compressors in the nuclear industry. The hydrogen in the machine is only exposed to the metal diaphragm that acts as a piston and is 100% leak free. There are no rider rings or piston rings that can cause contamination.
The special design of the 'head' of the compressor makes very high pressure ratios possible in a single stage machine. This allows us to reach 100 MPa at discharge from 5 MPa at suction with only two stages.
Howden diaphragm compressors are designed for pressures up to 300 MPa. A long lifetime is ensured by the fact that we use the demanding API618 standards as a guideline for design and manufacture.
We have created a modular range, which allows us to use standard components while at the same time maintaining the possibility to customise the package for each application.
Modularisation also allows us to reduce the lead time and cost of the compressor package, as it consists of parts that are ordered on a regular basis.
A cloud based monitoring system can be added to the compressor to make sure any malfunction is swiftly detected, or even prevented by early warning.
As the inventors of the technology, we have been at the leading edge of diaphragm compressor innovation for almost a century, constantly improving safety and performance.
Over 1500 Howden diaphragm compressors are operational in the field at this moment. Of these, more than 700 are used to compress hydrogen in various processes. Howden has supplied the first compressor for FCEV applications as early as 1992.
Our unique HIDS system provides constant real-time monitoring of diaphragm integrity and provides a fail-safe stop procedure and containment of process gas in the event of a breach, thus providing absolute safety in operation.
Our diaphragm compressors can be provided as fully tested skid-mounted packages ready for easy installation and problem-free commissioning, as well as in bare-shaft versions for integration in customer- specific packages.
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