‘It’s like a cross between a giant night storage heater and a thermos flask,’ says James Macnaghten, CEO of Caldera Heat Batteries Ltd. Caldera’s innovative heating solution uses a novel, heat-retaining material called Warmstone, which heats up using cheap off-peak electricity. Insulated in a vacuum, this heat can then be stored for more than three weeks, delivering plenty of hot water on demand.
The Warmstone heat battery can be used as a straight swap for conventional boilers: because it heats water to the same temperature as the boiler it replaces, the existing pipes and radiators in a building don’t need to be upgraded. Warmstone is designed for retro-fitting properties, and is especially well suited to those that are off the gas grid (and have been using oil instead), as well as those with solar panels (it’s a great way of storing energy from solar PV). In larger, older homes in particular, as well as other buildings such as offices and churches, Warmstone units can be a more sustainable, flexible and cost-effective option than conventional boilers.
With more than five decades of experience working on energy storage systems between them, the Caldera team knew that they had a potentially world-beating solution with Warmstone: innovative not just in the core material it uses but in the insulation it has, and the smart methods it employs in getting heat efficiently into and out of the units. What the company needed was funding, and so for over a year it has been working with Innovate UK EDGE & Exemplas Innovation and Growth Specialist Emma Douglas-Beet, who has helped Caldera refine its pitch as an investment opportunity and put the company in touch with potential investors.
Debut on crowdfunding platform
Having honed its offer, in June 2021 Caldera made a highly successful debut on British investment crowdfunding platform Crowdcube, exceeding its target and closing out at £1.57M in investor funding (it is now backed by a community of nearly 1,300 Crowdcube investors). Since then, the company has increased its turnover by £570K, and won further grant funding worth £300K.
For James Macnaghten, ‘I’ve found the interaction with Emma to be extremely helpful: she is very knowledgeable about the entire fund-raising process for early-stage companies, and she was able to introduce me to a number of investor groups and individuals involved in fundraising. Emma was particularly helpful as we prepared for crowdfunding. As a start-up you need people to practice on, honing your message and your presentation, and in Emma we found someone who is pragmatic and has great experience, but who wasn’t too close to our company already. I wouldn’t hesitate to recommend her.’