Around half of UK homes are rented, flats or too small for rooftop solar and a home battery. Rob Hallifax, co-founder of Windfall Energy, is building a plug-in battery for them: no installer, no roof, no garage. It charges when electricity is cheap, powers your home when it’s expensive, and saves around £250 a year.

Richard Leader and Rob talk through where that £250 comes from, the regulatory gap holding back plug-in batteries, battery safety, manufacturing hardware at small scale, and why energy companies could be the route to millions of homes.

Gains, Not Guilt is a podcast for climate tech founders about winning on commercial value, not carbon guilt. Stop selling the planet. Start selling the benefit.

Llewellyn Kinch, founder of Make My House Green, discusses the unique approach to solar installation, the customer experience, and the changing landscape of the solar market. The conversation delves into the business model, customer motivations, and the future of Make My House Green.

Takeaways

• Tech-first approach
• Customer-focused design
• Market changes and challenges

Chapters

• 00:00 Introduction to Make My House Green
• 01:09 Tech-First Approach to Solar
• 03:42 Customer Experience and Personalization
• 06:06 Market Changes and Challenges
• 08:49 Environmental Impact and Motivations
• 21:05 Regulatory Landscape and Financial Considerations
• 26:01 Future of Make My House Green

Cement production accounts for around 8% of global greenhouse gas emissions, and a good chunk of that comes from the fuel needed to keep kilns burning at 1,450°C, 24 hours a day. Buffy Price, co-founder of Gigaton Technologies (formerly Carbon Re), has spent six years building an AI control system that optimises that process for cement producers.

The numbers are big on both sides. Each plant reduces carbon output by 15,000 to 20,000 tonnes a year and saves between £1 million and £3 million in fuel costs. But as Buffy explains, the carbon reduction is almost never the reason a customer buys. Cement producers are running on tight margins in a genuinely difficult industry, and it's the cost line that gets the deal signed.

In this conversation, Richard and Buffy get into how Gigaton actually works inside a kiln, why Buffy walked away from an easier product decision that cost the company some early customers, how they're managing a land-and-expand model across Europe, India and soon North America, and what she's learned about choosing investors who won't push the company off course.

This is a founder conversation about building a genuinely commercial climate tech business, in one of the hardest, least glamorous sectors there is.