The Cambridge-based company will use the money to help increasesales volumes of its patented product.
The funding round was led by the current investor syndicate including Qi3 Accelerator, the Low Carbon Innovation Fund (LCIF), Synergy Energy, Martlet, and others, plus several new investors.
Isotera chairman Nathan Hill said: ‘This second funding round will enable us to grow our sales activity substantially and support a further cycle of product range developments. I’m delighted that our existing investors showed their support in this round, and welcome several new investors to the syndicate.
Isotera’s system uses a hub to convert mains electricity to high-frequency AC, supplying power for dozens of light fittings.