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The HTPEM (High Temperature Polymer Eloctrolyte Membrane) uel cell system developed by

Serenergy is the rst commercially available, low pressure, air-cooled HTPEM uel cell system in the

world. There are a number o major advantages o Serenergys HTPEM uel cells versus commonly

available LTPEM (Low Temperature Polymer Electrolyte Membrane) uel cells:

High system efciency o HTPEM uel cells. As a result o not needing the humidier, compressor and

radiator as in the LTPEM system, the HTPEM system is very simple. The Serenergy uel cell system uses less

than 4% or this base purpose, making this the uel cell system with the lowest parasitic power

consumption searchable. We term it The Power o Simplicity. Partly due to the low parasitic losses we

have achieved uel cell system eciencies o up to 57%. Most uel cell systems have an energy usage o

approximately 10-20% o the output, just to achieve operational status. The best LTPEM uel cell systems

have parasitic losses o 68%, but parasitic loss exceeding 10% are common.

Lower system cost o HTPEM uel cells. As a result o not needing the humidier, compressor and radiatoras in the LTPEM system, the HTPEM system is built using a very simple internal architecture reducing the

Balance O Plants (BOP) cost to approximately 25% o the uel cell stack cost. This is achieved by

eliminating a number o traditionally used components such as humidiers, pumps, compressors and

radiators. The uel cell itsel only requires a single air-an, similar to those used to cool CPUs in computers.

For LTPEM uel cell BOP components may cost up to 200% o uel cell stack costs.

HTPEM uel cells are highly tolerant to CO. CO is a known uel cell poison and is a result o using reorm

liquid uels. The CO content necessitates uel clean up which in turn means that use o reorm liquid uels

requires much cumbersome systems because o larger and thereore more costly systems. Due to the

elevated temperatures in HTPEM, hydrogen with a higher CO concentration can be used without the same

negative impacts on the perormance. This makes it possible to directly use hydrogen reormate originating

rom cheap, and easy to handle energy-carriers such as methanol, ethanol, diesel etc.

The HTPEM uel cell can tolerate up to 3% (30,000ppm) CO and up to 20ppm o sulphur without

permanent degradation. In comparison, LTPEM uel cell normally can tolerate less than 30ppm CO and less

than 1 ppm o Sulphur. This is a actor o 1,000 diference in CO tolerance. Because o the high operating

temperature, a PrOx reactor is normally not necessary. PrOx reactors are expensive, bulky and signicantly

lower the system eciency. The result is that very simple, lightweight and inexpensive reormers can be

used to produce hydrogen rom a broad range o energy-carriers including the choices listed above.

HTPEM uel cells is easier to control. Since HTPEM uel cells can be operated over a broader operatingwindow temperature-wise (compared to LTPEM uel cells) it is ar easier to control than a LTPEM uel cell

system.

High quality waste heat rom HTPEM uel cells.The waste heat needs to be hot to be o high quality. The

waste-heat rom a HTPEM uel cell (~155C) is thereore by denition o higher quality than waste-heat

rom a LTPEM uel cell (~70C).

The waste-heat needs to be concentrated in a usable directional stream. In Serenergys case more than 90%

o the waste-heat leaves the uel cell system through the exhaust-pipe and is thereore easy to utilize.

Since the waste-heat in Serenergys uel cell systems is o high quality and is conatined in a usable

directional stream it is easy, cheap and simple to recover some, or most, o the waste-heat using air-to-air

or air-to-liquid heat exchangers.

Advantages o HTPEM uel cells over LTPEM uel cells

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Fewer components in HTPEM uel cell systems:

No humidifer. There is no need or a humidier due to the composition o the Membrane ElectrodeAssembly (MEA) which results in a simpler, cheaper and more reliable uel cell system.

No compressor. There is no liquid water in a HTPEM MEA and thereore there is no need or a compressor.This urther reduces system complexity, cost and noise level while greatly increasing uel cell systemefciency. Due to the high operating temperature, heat can easily be removed rom the uel cell system.

No radiator. There is no need or a liquid cooling loop. Assuming an ambient temperature o 40C, aLTPEMFC operating temperature o 70C and a HTPEMFC operating temperature o 160C, then one hasa t o 30C or the LTPEM system compared to a t o 120C or the HTPEMFC. The t o a HTPEMFC isthereore 400% more than or the LTPEMFC. The result is that there is no need or a complicated, bulky and

expensive liquid cooling system. A simple, small and inexpensive an can be used or cooling instead. Theparasitic loss rom the an reaches a maximum o 3.5%.

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