This ‘sand’ battery stores renewable energy as heat

A company in Finland has created an an unusual storage solution for renewable energy: One that uses sand instead of lithium ion or other battery technologies. Polar Night Energy and Vatajankoski, an energy utility in Western Finland, have built a storage system that can store electricity as heat in the sand. While there are other organizations researching the use of sand for energy storage, including the US National Renewable Energy Laboratory, the Finns say theirs is the first fully working commercial installation of a battery made from sand.

Similar to traditional storage systems for renewables, Polar’s technology stores energy from wind turbines and solar panels that isn’t used at once. To be precise, it stores energy as heat, which is then used for the district heating network that Vatajankoski services. Sand is inexpensive and is very effective at storing heat at about 500 to 600 degrees Celsius. Polar says its technology can keep sand “hotter than the stoves in typical saunas” for months until it’s time to use that heat during Finland’s long winters. 

As the BBC explains, the resistive heating process used to warm the sand generates hot air circulated inside the structure. When it’s time to use the stored energy, the battery discharges that heated air to warm water in the district’s heating system, which is then pumped into homes, offices and even pools. At the moment, Polar’s sand battery only serves a single city, and it’s still unclear whether the technology can be scaled up. The BBC also says that its efficiency “falls dramatically” when it comes to returning electricity to the grid instead. It’s early days for the technology, though, and other companies and organizations might be able to find solutions for those issues. 

We’re heading for a messy, and expensive, breakup with natural gas

Russia’s invasion of Ukraine has exacerbated a number of fault lines already present within the global energy supply chain. This is especially true in Europe, where many countries were reliant on the superstate’s natural resources, and are now hastily …

Lightyear’s very pricey solar-powered car will go into production in late 2022

EV startup Lightyear debuted its first solar-powered vehicle this week, a sleek sedan called the Lightyear 0. The company gave us a peek at a production prototype of Lightyear 0 in 2019, and at first glance, not much has changed. The car is essentially an unconventional hybrid equipped with both a conventional 60-kilowatt-hour EV battery pack and solar panels on its roof, hood and hatch. The solar panels on the Lightyear 0 will charge automatically whenever the car is exposed to the sun — it doesn’t matter if it’s parked or driving.

The Lightyear 0 isn’t as much solar-powered as solar-assisted. In order to drive for long distances, the vehicle has to tap into its battery reserve. The car’s solar panels can provide 44 miles of range per day in a sunny climate, whereas its EV range is 388 miles. But for drivers with exceptionally short commutes or those who need their vehicle infrequently, the Lightyear 0 could allow them to no longer spend money on gas or charging. The company claims that those with a daily commute of 22 miles can drive the Lightyear 0 for two straight months in the Netherlands summer without needing to charge. Drivers in sunnier climates can go for longer. Lightyear claims that the sun can provide the Lightyear 0 with anywhere between 3,700 to 6,800 miles of range annually.

It’s important to note that Lightyear 0 owners will need to drive for a significantly long time in order to justify the vehicle’s purchase as a cost-saving measure. The Lightyear 0 will cost €250,000 (which amounts to roughly $263,262 USD), and the company only plans on making 946 units. But a more reasonably-priced vehicle is on the way. Lightyear recently also unveiled a prototype of a $33,000 solar-powered car, which is scheduled to go into production by 2025.