General Information

Why do I need an EFOY COMFORT fuel cell?

The EFOY COMFORT fuel cell is a fully automated battery charger that is quiet, simple and environmentally friendly, operating as a power generator in mobile homes, boats or cabins.

What is the EFOY COMFORT fuel cell designed for?

The EFOY COMFORT fuel cell has been designed and developed for private operation in mobile homes, boats or cabins. If you need a fuel cell for commercial or professional use, SFC can provide the ideal solution with its EFOY Pro range of products.

What is a fuel cell?

A fuel cell is a galvanic cell that converts the energy created by the chemical reaction between a constant stream of fuel and an oxidant into electrical energy. The underlying principle is an electrochemical process that is also known as "cold combustion". It is in principle the reversal of electrolysis. A fuel cell is not an energy store but a converter that generates electricity. The energy required to produce electricity comes from the fuel.

How does the EFOY COMFORT fuel cell work?

The EFOY COMFORT fuel cell converts the fuel in the fuel cartridge directly into electrical current. Thanks to this direct conversion, which is performed with no moving parts, silently and environmentally friendly, the fuel cell is extremely efficient and clean.
How it works.

Can I use the EFOY COMFORT fuel cell in hybrid operation with a solar energy system?

Yes. A lot of our customers do this. The fuel cell switches on automatically when there is insufficient sun available for the solar energy system. There is also an intelligent hybrid system for use with mobile homes developed in collaboration with Büttner Elektronik.

Why should I buy an EFOY COMFORT fuel cell when there are solar cells?

Solar energy is a fascinating subject, but solar energy systems only work when the sun shines direct on the solar module, i.e. without any shadowing effects and at the correct angle of incidence. This is not the case in most situations e.g. because of clouds, at night, due to fog, rain, snowfall, in the shade of trees etc. An EFOY COMFORT fuel cell will supply between three and ten times the amount of electricity as a solar energy system with the same output over the course of a year. To produce the same amount of electricity as an EFOY COMFORT 80 (40 W) with solar power, depending on the country and time of year, you would need a solar energy system with an output of between 120 and 400 Wp.

Why should I buy an EFOY COMFORT fuel cell when there are petrol- or diesel-powered generators?

Generators are very loud and do not just disturb your own relaxation but also that of your neighbours. The emissions that they produce cause an unpleasant smell and are environmentally harmful. In contrast, the EFOY COMFORT is as quiet as a whisper and environmentally friendly – which is good for you and for the environment.

How many fuel cells are in use and are customers satisfied with the EFOY fuel cell?

SFC has already sold more than 45,000 EFOY fuel cells, which are in use day in, day out. The total operating time of all units amounts to over 10 million hours.
In a survey of 955 EFOY owners, 93% of those questioned were satisfied with their EFOY fuel cells and would recommend them to other potential customers.

Why are there several models in the EFOY COMFORT range?

Customers' performance requirements vary depending on usage profile, personal needs, type and power consumption of the appliance and environmental conditions etc. EFOY products with varying levels of output offer the customers the choice and opportunity to purchase the fuel cell that matches their needs.

Which EFOY fuel cell matches my needs?

Please have a look here Which model?

Installation / operation

How is the EFOY COMFORT installed?

Installation is performed by an authorised dealer, or the unit comes pre-installed with your boat or mobile home.
Dealer search.

What must I watch out for when installing?

Make sure there is an adequate air supply and sufficient ventilation for waste heat and spent air. Please also ensure that there is enough space for the fuel cartridges and the unit itself. You can refer to the User Manual for more details.

Can I retrofit an EFOY COMFORT fuel cell?

An EFOY COMFORT fuel cell can be easily installed at any time. It is simply connected directly to a normal battery. Please contact your EFOY dealer for more information.

Do I need an additional charge controller for an EFOY COMFORT fuel cell?

No. The EFOY COMFORT incorporates its own charge controller.

Can I connect electrical appliances direct to the EFOY COMFORT fuel cell?

No. The EFOY COMFORT fuel cell is a battery charger. Electrical appliances are supplied with power by the battery.

What types of battery can I charge with an EFOY COMFORT fuel cell?

An EFOY COMFORT fuel cell is an automatic charger for 12 V lead-gel, glass-mat, AGM, lead-acid or from SFC certified Lithium Iron phosphate (LiFePo4) batteries with 12V.

Can I charge more than one battery (e.g. 2x100Ah)?

Yes. We recommend that 2 x battery capacity is less than the total charging capacity of the EFOY fuel cell.

Can I use an EFOY fuel cell to charge a lithium battery?

Yes. The EFOY COMFORT fuel cell with firmware version 15.11 or higher can be used to charge lithium iron phosphate (LiFePO4) batteries of dedicated manufacturers.

Is it possible to adjust the switch-on/switch-off thresholds?

Yes. All the fuel cells in the new EFOY COMFORT series allow the switch thresholds to be adjusted via the control panel. Your dealer can make the adjustment.

Is there a risk that the batteries can be exhaustively discharged?

No. An EFOY COMFORT fuel cell has a mechanism to prevent exhaustive discharge and will activate even when switched "OFF" in order to protect batteries from exhaustive discharge.

What exhaust gases does an EFOY COMFORT fuel cell produce?

It produces very small quantities of water and carbon dioxide. The fuel cell produces as much spent air at peak load as a human does.

How much waste heat is produced?

The level of waste heat depends on the ambient temperature, which is why there is no simple answer to the question. The heat (measured in watts) is approximately three times as high as the electrical energy (rated power) generated by the unit. For example, an EFOY COMFORT 80 fuel cell produces approximately 120 W of heat.

Does the exhaust air contain just water and CO2?

The exhaust air may also contain traces of methanol and methanol-based waste products. The quantities and concentration of these are below the legal thresholds. IMPORTANT: Always expel exhaust air into the open. Inhaling the exhaust air or drinking the water may be harmful to your health. The exhaust air contains no CO (carbon monoxide) or NOx (nitrogen oxide).

Can an EFOY fuel cell be operated in a moving vehicle?

Yes. The EFOY COMFORT fuel cell is approved for use in motor vehicles. Leading vehicle manufacturers install fuel cells in their vehicles as standard.

What should I do in the event of an accident?

Do not switch the fuel cell on. The unit must be returned for inspection to check that it does not leak and that it operates correctly. Please contact the EFOY service team.

What safety standards does the EFOY COMFORT fuel cell meet?

The EFOY COMFORT fuel cell meets the highest standards of safety and quality, including regulations governing installation in motor vehicles. It is the world's first fuel cell to be certified in accordance with ECE-R10 (installation and operation in motor vehicles), CE and "Safety-tested and production-monitored fuel cell system" awarded by TÜV SÜD.

Consumption / Fuel Cartridge

How much fuel does the unit consume?

Consumption depends on the electrical appliances. Consumption is currently around 0.9 l per kilowatt hour.

Is consumption lower for smaller fuel cells?

No. Consumption is dependent on the electrical power consumed in kWh. It is only daily consumption that depends on the maximum output of the fuel cell.

How long does an M5 or M10 fuel cartridge last on average?

Assuming an average requirement of 33 Ah/day (400 Wh/day):
- one M10 will last approx. 4 weeks
- one M5 will last approx. 2 weeks

How many fuel cartridges will I need in a year?

EFOY customers generally need 2-3 M10 fuel cartridges per year in normal use.

Are EFOY fuel cartridges approved for transportation?

EFOY fuel cartridges were designed to meet the highest safety requirements from the very beginning. Fuel cartridges are also approved and labelled for road, sea and air transport.

Can an EFOY fuel cell be operated with other fuels or fuel cartridges?

No. It is not allowed to use fuels or fuel cartridges other than the original fuel cartridges supplied by SFC Energy AG. IMPORTANT: Using contaminated methanol will result in damage to the product and invalidate the warranty.

Why is it not possible to refill the fuel cartridges (either myself or through a third party) ? --> When will there be a refill solution available for fuel cartridges?

The law stipulates that EFOY fuel cartridges may only be sold in sealed containers for safety reasons. Accordingly it is not permissible in law to provide a refill solution. In addition, the costs and energy overhead involved in refilling would not justify the benefits.

How long do fuel cartridges keep?

There is a label on the back of every fuel cartridge indicating its use-by date. Shelf life is generally 3 years.

Why does SFC use methanol and not gas or some other form of fuel?

SFC has focused on the proven direct methanol fuel cell. This technology does not require the fuel to be converted into hydrogen in a very complex and elaborate process as is the case with e.g. propane or butane gas. A further advantage is the high energy density of methanol and the use of fuel cartridges as means of storage. One M10 cartridge weighs only 8.4 kg (18.5 lbs)and provides a capacity of 920 Ah (which corresponds to more than 250 kg (550 lbs)of lead batteries).


What is the temperature range in which the fuel cell operates?

We guarantee safe operation in an ambient temperature range of -20 °C to +40 °C (-4° F to +104° F).
Should you require a power source to operate under more extreme conditions, please contact sales@sfc.com.

Is it possible to run at temperatures below 0°C (32°F)?

Yes. The fuel cell has an intelligent frost protection mechanism which ensures that it function when used at even very low temperatures.

What happens above +40 °C (104 °F), which is considered to be the maximum temperature?

The unit interrupts the charge function and starts once more fully automatically once the temperature falls. This prevents damage to the fuel cell. Should you use the fuel cell at high temperatures for long periods of time, please contact sales@sfc.com.

Why do you recommend the removal of the fuel cell from vehicles during winter months?

We only recommend removal if you do not require the fuel cell for longer than 2 months (for example in winter storage with a power supply). Removal and frost-free storage can save fuel.

How does the frost protection mode work?

The fuel cell has an intelligent automatic frost-protection mechanism. It keeps itself warm when temperatures fall below 3 °C (37 °F) when it is connected to a functioning battery and has a supply of fuel.

How much does the frost protection mode consume?

The fuel cell requires approx. 5-10 litres of methanol for dedicated frost protection mode during a five-month winter period in Central Europe.

What must I do if the fuel cell freezes?

If the fuel cell freezes despite all precautions, allow it to thaw switched off in a warm environment over a period of approx. 24 hours before putting it into operation. Please note that a fuel cell's efficiency may decrease when allowed to freeze repeatedly.

Inclination angle

What is the maximum angle of tilt for EFOY fuel cells? Is there a graphic of the EFOY COMFORT fuel cell?

The unit can be operated for a sustained period of time at an angle of tilt of up to 35° longitudinally and up to 20° laterally.

What happens if the fuel cell tilts further than this?

The fuel cell will switch off and will report an error when switched back on again. Please follow the instructions on the display.

Purchase questions

Where can I buy an EFOY COMFORT fuel cell?

We recommend that you only purchase a fuel cell from authorised EFOY dealers or EFOY Inside/EFOY Ready partners. You can find here a list of the dealers here.

How much does an EFOY COMFORT fuel cell cost?

Your authorised EFOY dealer can tell you the current price.

What is included in delivery?

Scope of delivery here.


Does SFC provide a warranty for the EFOY COMFORT fuel cell?

The EFOY COMFORT fuel cell meets the highest quality standards. We guarantee it. For more details go to Warranty.

When does warranty cover start?

The purchase date of the new fuel cell on the invoice and its registration with SFC determine the start of warranty cover.

Why do I have to register?

Registration ensures that we can provide you with the latest information on a regular basis, for example when there is a new firmware update. In addition, SFC will have all the necessary details if you require service, which means that we can process a case faster.


Can an EFOY COMFORT fuel cell be repaired if it is defective?

Yes. We can repair your fuel cell at our location in Brunnthal near Munich when necessary. For futher information please see Service.

Is it possible for me to buy replacement parts and install them myself?

No. The unit must never be opened.

How long does a repair take?

Repairs can generally be performed within a few working days. On top of this there is the time required for transportation and the time until the quotation is approved.

How much do repairs cost?

Repair costs depend on the components involved.

Why should I perform a regular update?

A new update is not essential, but fuel cells are being continuously improved and you are welcome to benefit from this. Further information can be found at Updater.

Why do I need the service fluid? What is it exactly?

Service fluid is delivered with your EFOY fuel cell. Thanks to SFC's patented water recovery system, fluid is recovered in a closed circuit. Over a long period of operation with high external temperatures a part of this fluid may evaporate, and the fuel cell will indicate that it requires service fluid. It is recommended to always have a bottle with you. Never fill up more than one bottle, and only when the fuel cell indicates that it really needs it (via the control panel).

EFOY 1. Generation / EFOY COMFORT

Can the new EFOY COMFORT fuel cell also be operated using the old control panel?

No. The new EFOY COMFORT fuel cell can only be operated with the new control panel designed for the EFOY COMFORT series.

I have a first-generation EFOY fuel cell. Can I use the old cabling?

Yes. You do not have to install new cables, but you may have to exchange the battery fuse and adjust it to the output of the EFOY COMFORT fuel cell.