Wander through the Himalayas and you might be surprised to catch a 5G mobile signal near Ganbala, 71 kilometres southwest of the Tibetan capital Lhasa. The signal, courtesy of a transmitter installed at a Chinese radar post in 2021, is growing testament to our ability to bring telecommunications to remote regions.
And that ability is largely thanks to a power technology that has been around for more than 100 years. Many of the world’s 10 million or so mobile base stations, along with innumerable other remote devices, are powered by diesel generators that have barely changed since they first came to prominence in World War II.

There are good reasons for this longevity. Diesel fuel is readily available around the world and the gensets are robust, reliable and relatively cheap to buy.
The global market for diesel gensets was estimated to be worth more than $16 billion in 2023 and is expected to see a compound annual growth rate of almost 10% up to 2030, according to Grand View Research. But there are reasons why the diesel genset might no longer be the power technology of choice for some off-grid applications.
For all its benefits, diesel gensets also have significant drawbacks. Even the most efficient models have significant running costs and need refilling and maintaining at regular intervals. And diesel is usually cheap compared to other fuels, it is also subject to volatility.
Over the last five years, costs for US Gulf Coast ultra-low sulphur No 2 diesel have ranged from $0.54 to $5.30 a gallon—an almost tenfold change. Another worry is that the gensets and the fuel are prone to theft, with diesel losses in the telecommunications supply chain said to range from 15% to 30%.
Diesel is not particularly great for the environment, with spills contaminating land and water and exhaust fumes causing air pollution. And an increasingly greater cause for concern is carbon emissions.
A diesel generator might emit up to 0.93 tonnes of carbon dioxide per megawatt-hour of energy, or more than twice the average level of emissions you would get from using electricity produced for the US grid.
Given these drawbacks, it is hardly surprising that a range of competing—and complementary—technologies have emerged to challenge diesel’s dominance of off-grid power markets. Most can help reduce fuel consumption by working alongside gensets—or replace the diesel units altogether. An obvious example is solar power.

An alternative to diesel
Solar panels are cheap to buy and install, have minimal maintenance requirements and can provide clean power for decades. If tied to a genset in a hybrid system, solar can take care of power demand during daylight hours and greatly reduce the need for diesel fuel and generator maintenance, as well as reducing emissions.
The benefits can be extended even further with the addition of lithium-ion batteries to capture excess solar generation and use it for overnight power. A 2021 comparison of genset-only and diesel-solar-battery hybrids in Nigeria found the latter yielded a reduction of between 24% and 55% in the levelised cost of energy.
In theory, the solar power in such hybrids could be replaced by other sources of renewable energy, such as mini hydro power or wind. But the availability of hydro power is limited in many remote locations, and wind power might be too intermittent for use in applications that require a constant source of power.
Another option is to bypass diesel altogether and simply rely on solar and batteries for off-grid power. This is an increasingly attractive model for microgrids as batteries come down in price.
But it relies on there always being sufficient battery capacity to supplement times of low solar production, which may be a concern for industries where continuous availability is important, such as in telecommunications.
But technology is now able to offer cleaner and more reliable alternatives to diesel even for high-uptime applications such as base station power provision. The technology in question is a fuel cell, a device that uses fuel to create electricity through electrolytic processes rather than combustion.
Fuel cells can operate with practically no noise or atmospheric pollution and at high levels of efficiency, allowing for long-term operation with relatively little fuel consumption. Most fuel cells today use hydrogen as a fuel, so they produce no carbon emissions—only water.
Under a cooperation agreement with the German technology developer Siqens, Pacific Green is offering a fuel cell model that uses methanol as a hydrogen carrier. Unlike hydrogen, methanol is easy to store and handle and is readily available on a commercial basis around the world.

Although it is a carbon molecule, the efficiency of its use in the Siqens fuel cell means it can reduce off-grid power system CO2 emissions by 70% compared to diesel, which, coupled with zero NOx and particulate emissions, make the units much more environmentally sustainable than gensets.
Efficiency is aided by the fact that the Siqens fuel cell comes with 6 kW to 15 kW of lithium-ion battery capacity, giving the system a total power of up to 40 kW. Energy is provided by methanol fuel, with 100 litres delivering up to 160 kWh of electricity.
100% Emissions-free energy
Each fuel cell unit comes with a weatherproof enclosure and lockable doors, and is optimised for transportation by truck, forklift, crane or pick-up. The units can operate in almost any environment on land, and have connectivity for remote control, monitoring and automatic alarms.
Designed to power critical infrastructure in unattended operation for weeks on end, the fuel cell is plug-and-play in terms of installation and only requires maintenance every 3,000 hours, around 10 times the amount required for a diesel genset. It operates with a sound of just 45 decibels, making it 20 times quieter than a traditional generator.
This technology can replace gensets today in just about any off-grid system, from the power for a telecommunications base station to the electrical supply for a remote mine, wind farm or construction project.
And the beauty of the fuel cells is that they will operate equally well on methanol from natural gas—the main source of supplies today—or produced as an e-fuel from electrolytic hydrogen and captured carbon, which promises to offer 100% emissions-free energy tomorrow.
Publish date: 27 January, 2025