Phasing Out Diesel, One Solar Train At A Time

solar train. Credit: concern over the relationship between climate change and fossil fuels have companies around the world looking for ways to reduce the carbon footprint of long-distance travel. The year 2019 saw one of the most significant breakthroughs in solar-powered travel so far — the world’s first solar-powered rail line in the United Kingdom.

Here is everything you need to know about solar-powered trains and railways, including where the technology is right now, plus how experts think it will be used very soon.

The World’s First Solar-Powered Railway

Solar-powered trains are propelled by energy from solar panels placed on or near railway tracks.

The rail line, which is powered by 100 track-side solar panels, was developed as a joint project between British climate charity Possible (formerly 10:10 Climate Action) and Imperial College London.

Right now, the solar panels aren’t powering the entire rail yet and are only responsible for keeping the lights and signaling systems along the line on. In the future, however, they may help power the electric trains that run on the line.

Network Rail, the organization which manages most of the rail in the U.K., also hopes to eventually deploy the technology on lines across the country.

The track isn’t the first instance of trains powered by solar energy. Back in 2017, an Australian rail company launched the first solar-powered train. However, this is the first time a rail line has been powered directly by solar panels, rather than by pulling energy from the grid.

Where Solar Rail Goes From Here

There are a few different reasons why rail companies are showing interest in rail lines powered directly by their own solar arrays.

One of the biggest factors driving the change is growing pressure on the electrical grid that delivers power from renewable energy sources to rail lines.

Right now, rail companies are beginning to sundown existing trains powered by onboard diesel engines, further increasing the energy they need to keep their trains moving. Network Rail, for example, has started to phase out its diesel trains and replace them with electrified trains — meaning more money spent on energy and more strain placed upon the grid.

Energy production that sends energy directly to railways — like track-side solar arrays connected to rails by protected wires and cables specially made for renewable energy — could make British railways much more grid-independent. This direct energy would also be cheaper than electricity from the grid, saving rail companies money.

Riding Sunbeams, the research team behind the solar rail project, estimated that solar rail arrays could provide as much as 15 percent of the energy needed by commuter lines in major British cities like Sussex, Wessex and Kent. The team’s research also found that nationwide adoption could save rail companies as much as $5.8 million every year.

However, it’s likely to be many years before we see solar-powered train lines deployed at scale. Network Rail will likely want to pilot-test running trains on track-side solar panels before committing to the technology.

There are also a few different downsides to solar power that may slow down adoption. Because solar panels can’t provide round-the-clock energy, rail lines that rely on solar will need to be equipped with batteries. These batteries are expensive and have a limited capacity, which means rail companies will need to continue relying somewhat on the grid and invest in costly batteries simultaneously.

How Solar Energy May Change Railways

Rail companies wishing to transition away from fossil fuels are looking to alternative energy sources. That includes solar rail, which is powered directly by photovoltaic panels along rail lines. This one train line in the U.K. is already powered by solar panels. The research team behind the project has also estimated significant savings if rail companies make the switch to solar.

However, the adoption of solar rail may be delayed by its inability to deliver 24/7 energy and its reliance on costly batteries.