What else you should know about Sunfire-Remote

There is no one-size-fits-all solution for off-grid systems. We have collected the most frequently asked questions. For everything else, get in touch with our experts.

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Operation Mode

Is Sunfire-Remote suitable for continuous operation?

Yes. Basically, our devices are developed for continuous operation. Therefore, they also achieve the longest stack life under these conditions. Frequent and rapid startup and shutdown, on the other hand, can have a detrimental effect on the performance. This is because the stacks in the core system reach temperatures of around 800 °C. Please contact us if you intent to integrate Sunfire-Remote to a frequent start-stop operation.

Can the devices be used to provide backup power?

Yes. You can secure your application with Sunfire-Remote, e.g. in case of a prolonged power failure. The maximum duration of the bridging time is determined by the amount of stored fuel. The main advantage over diesel gensets is the significantly lower maintenance and servicing costs for the generator and fuel tank.

It should be noted that the Sunfire-Remote is based on high-temperature solid oxide fuel cells (SOFC). They reach temperatures of about 800 °C in the core system. A start-up process takes between 4 and 8 hours, depending on the device type and ambient temperatures. During this time, a battery must provide the energy for the customer load and the start of the Sunfire Remote. Our experienced team will be happy to assist you with design questions.

Is it possible to monitor the operation remotely?

This is easy to implement. Sunfire-Remote has an IP gateway which can be integrated into the customer network. A combination with mobile routers is also possible.

What types of fuel are being used?

Sunfire-Remote is currently approved and certified for use with propane and natural gas. This means it can be used with piped natural gas, CNG or with LPG with propane content of >95 % as a logistical fuel in cylinders and tanks. Inside the unit, a reformer converts the fuel into a hydrogen-rich gas (reformate), which is then electrochemically converted in the fuel cell stack.

We recommend biogenic propane from renewable resources or synthetic e-propane from renewable electricity for sustainable and emission-free operation.

How much fuel do the power generators consume?

Our fuel cell units have an electrical efficiency of approximately 30 %. As a rule of thumb, 3.33 kWhchem of fuel is required to generate 1 kWhel. Also, there is 12.9 kWh of chemical energy stored in 1 kg of propane. Thus, about 3.87 kWhel can be generated from 1 kg of propane.

Does the device also work with hydrogen?

The devices are currently not suitable for operation with pure hydrogen. This is particularly since hydrogen cannot easily be used as a logistical fuel.

To store the same amount of chemical energy as propane, hydrogen needs more than five times the volume and the cylinders have nearly 8 times the weight related to the generated power. In many off-grid applications, there is not enough space to store such amounts of fuel.
In addition, transport, storage and refueling with hydrogen are currently subject to strict safety regulations.

Nevertheless, operation with hydrogen will be possible in the medium term. Sunfire is developing designs to enable its fuel cell devices to be operated in hydrogen networks in the future.

How cost efficient is Sunfire-Remote?

We keep operating costs low. Because our fuel cells run unattended for up to 10,000 hours, maintenance and service costs are unbeatably low. The high efficiency also leads to OPEX reduction. Another positive aspect is that the fuels used are available at low cost almost everywhere in the world.

We will be happy to support you with the profitability calculation for your application!

Installation & Service

How to install Sunfire-Remote?

Our customers appreciate the simple installation. To put the units into operation, only the exhaust pipe, the gas supply and the battery need to be connected. For Sunfire Remote 900, a cooling circuit is also required. After all connections have been made, the unit can be switched on directly and monitored via the integrated IP interface.


When does Sunfire's liability for defects begin?

The liability for defects begins at the time of installation and commissioning, but no later than 3 months after delivery.

Which material defects are covered by liability?

Sunfire is liable for defects caused by material or production faults within the framework of the statutory liability for material defects in accordance with the General Terms and Conditions of Sale and Delivery.

Download General Terms & Conditions

How long is the liability for defects valid?

The liability is applicable for a maximum of 2 years or 15,000 operating hours with a maximum of 30 cold starts (heat-up cycles) during the service life of the core module – whichever occurs first – within the scope of the statutory liability for material defects.

Individual Adaptions

How can Sunfire-Remote generate even more power?

If your energy demand is significantly higher than the generated energy of one device, two units can be operated in parallel. In this case, we match the settings precisely to the specific requirements.

The coupling is uncomplicated. In most cases, neither a disconnector nor an interface between the devices is required. They run completely independently by monitoring the State-of-Charge (SOC) of the batteries.

Can the devices be connected in parallel to further increase reliability?

In remote areas with limited seasonal access, it may make sense to have additional backup. To further increase reliability, two units can be connected in parallel. In this case, the primary unit is configured for permanent power. The secondary unit will only turn on if the other device is no longer able to charge the battery. This unlikely event may occur due to a fault or degradation at the end of the core system's life.

Can Sunfire-Remote be combined with photovoltaics?

Many of our customers use Sunfire-Remote in photovoltaic hybrid systems. Our units are well suited for this type of application. Nevertheless, such installations require careful planning. All system components must be well coordinated to permanently ensure reliable operation. Usually, the photovoltaic system generates the power needed during the summer while the fuel cell handles the operation in the winter, when insolation is low. That interaction reduces fuel consumption and logistical effort. As the operating hours of Sunfire-Remote decrease as well, the maintenance intervals and the lifetime of the fuel cell core system are extended.

Can Sunfire-Remote be combined with wind turbines?

Hybrid installation with small wind turbines is not recommended due to the high volatility of wind generation.

Sunfire-Remote FAQ


Consult our experts

Are you looking for upgrading your off-grid power system or would you like to find out more?

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