Episode 105: Liz Allan and Johan du Plessis - Transforming Home Heating with tepeo's ZEB and Thermal Storage

Episode 105: Liz Allan and Johan du Plessis - Transforming Home Heating with tepeo’s ZEB and Thermal Storage.

Liz Allan speaks to Johan du Plessis, CEO and founder of tepeo, a company revolutionising home heating with its groundbreaking product, the ZEB, a zero-emission boiler. Johan delves into the innovative concept of storing cheap electricity from the grid into a high-density thermal battery, offering a fresh alternative to traditional heating systems. They discuss the urgent need for diverse and adaptable home heating solutions to tackle domestic carbon emissions in the UK. Johan sheds light on the barriers and misconceptions surrounding heat decarbonisation, emphasizing the shortcomings of the one-size-fits-all approach.

Johan du Plessis Bio:
Johan du Plessis began his career as an engineer with a strong oil and gas industry background. He worked internationally with BP, involving projects in the Shetlands and Korea. In 2014, seeking a more meaningful direction in his career, Johan undertook a global cycling journey that inspired him to shift his focus towards solving pressing energy issues. During his consulting years, Johan became deeply engrossed in the challenges of managing low-carbon electricity grids amid the transition from centralised generation to renewables and decentralised energy sources. His experiences and insights fuelled his commitment to addressing these critical issues, driving his career toward finding innovative solutions for a sustainable energy future.

Johan du Plessis Links:
Website: https://www.tepeo.com
Twitter: https://x.com/tepeoheat
Instagram: https://www.instagram.com/tepeoheat
LinkedIn: https://www.linkedin.com/in/johan-du-plessis

Episode Keywords:
Thermal batteries, cheap electricity, home heating, domestic carbon emissions, heat pumps, decarbonisation, innovative heating solutions, fiscal support, boiler upgrade subsidies, zero-emission boilers, high-density thermal storage, renewable sources,

Transcript

Liz Allan [00:00:01]  

On today's episode, I'm really pleased to have Johan Du Plessis. He's the CEO and founder of Tepeo. They're based in Winnersh, which is just a 15-minute drive away from me in Reading, but we only realized this recently. Johan, thank you for joining me.

Johan du Plessis [00:00:52]

Thanks, Liz. Great to be with you.

Liz Allan [00:00:56]

So, just to give some background, you were previously head of Smart Heat at Ovo Energy. But as CEO, you founded Tepeo in 2018. Could you tell us a bit more about Tepeo?

Johan du Plessis [00:01:18]  

I started my career in engineering, originally in oil and gas with BP, working globally, including the Shetlands and Korea. In 2014, I decided I wanted to focus on solving environmental problems, so I left BP and cycled around the world. After that, I went into consulting, focusing on energy and other sectors. I became obsessed with how to manage low-carbon electricity grids as we move from centralized generation to renewables. The challenge was how to match electricity use with when it's available, requiring flexibility and price signals to coordinate it. I joined a company called VCharge, which was later acquired by Ovo. At Ovo, we looked at the problem of heating, and that led to the creation of Tepeo and the Zero Emission Boiler (ZEB).

Liz Allan [00:03:38]

So, ZEB was born out of your idea. It's an electric boiler, right? How did the design come about, and how long did it take to develop?

Johan du Plessis [00:04:25]

The concept began with high-density thermal storage. We needed a solution for homes that couldn't accommodate heat pumps, which work for most homes but not all. The idea was to make heating entirely flexible, using electricity from the grid when it was cheaper or more renewable, store that heat, and use it for central heating. I designed the initial prototype using my engineering background and tested various materials, configurations, and control methods. We started in June 2018, spent 18-24 months prototyping, and tested many thermal storage materials. We raised funding, built a team, and developed a back-end infrastructure to connect these products in the field.

Liz Allan [00:06:42]

Wow, so ZEB is for homes without space for a heat pump, but heat pumps aren't for everyone anyway, right? What's the size of the boiler?

Johan du Plessis [00:07:13]

The ZEB is like a smart heat battery, about the size of a washing machine, and is a drop-in replacement for a fossil fuel boiler. It connects to existing pipes, requires minimal changes, and provides high-temperature heating without needing to change radiators. It doesn't need outdoor space, so it's suitable for homes without it. It’s designed for the median home by heat demand, like a 2-3 bed semi-detached or terraced house. 

Liz Allan [00:08:28]

And it stores heat during cheaper times?

Johan du Plessis [00:08:29]

Yes, it stores heat efficiently with heavy insulation and releases it in a controlled way to the heating system. It's similar in concept to old storage heaters, but much more efficient and suited for central heating. We often describe it as a heat battery.

Liz Allan [00:10:51]

Very clever! I love talking to innovators, and you certainly are one!

Johan du Plessis [00:11:05]

Thank you. The heating sector hasn't seen much innovation, which is one reason I decided to do this. There's been a lack of change despite the urgent need to decarbonize heating.

Liz Allan [00:11:30]

Heating accounts for 70% of UK domestic carbon emissions, right?

Johan du Plessis [00:11:59]

Yes, and if we're serious about reducing emissions, we need to tackle heating. People like Robert Llewellyn have been great in promoting these technologies, but it’s not a one-size-fits-all solution. Our product addresses a specific need.

Liz Allan [00:13:20]

So, what are the barriers to heat decarbonization, specifically related to your product?

Johan du Plessis [00:13:50]

There are many, from VAT relief only applying to heat pumps to subsidies that don't cover our products. We don't qualify for schemes like the boiler upgrade subsidy, which is currently £7,500 for heat pumps. This makes our product relatively more expensive. Our installed cost is around £8,000, which includes VAT, but we could reduce that significantly with better support. Other barriers include levies on electricity that don't apply to gas, making electricity more expensive. The whole market structure needs reform to drive the right behaviours.

Liz Allan [00:16:55]

Do you think the new government will integrate your product into the current incentives?

Johan du Plessis [00:17:40]

I hope so. There's optimism with the new government. Ed Miliband seems genuinely supportive of decarbonization. He mentioned extending the boiler upgrade scheme to more homes, and we hope this includes products like ours.

Liz Allan [00:20:33]

Let's hope so! You mentioned gas and electricity decoupling. Can you explain that?

Johan du Plessis [00:21:11]

There are levies applied to electricity but not gas, which artificially inflates electricity costs. Also, the price of electricity is often tied to the price of gas because gas turbines are still used to generate electricity. To decarbonize further, we need to incentivize flexibility in energy use, making pricing more dynamic based on supply and demand.

Liz Allan [00:23:01]

Absolutely. So, do you still face negativity around these types of products?

Johan du Plessis [00:23:31]

Yes, but it's improving. The gas industry has pushed hydrogen for years, creating misconceptions. When people’s boilers break, they hear from installers that they should wait for hydrogen, which is misleading. The heat pump industry also has issues with setting overly high efficiency expectations, leading to disappointment.

Liz Allan [00:28:47]

I see. So, tell us about your network of approved installers and the training you provide.

Johan du Plessis [00:28:51]

We have a network of Tepeo Pros, mainly gas and oil boiler installers. They can transition to installing our product with just a few hours of online training. This leverages their existing skills while allowing them to offer a low-carbon solution to their customers.

Liz Allan [00:36:25]

That’s great, especially in helping transition to low-carbon technologies. How quickly can ZEB be installed?

Johan du Plessis [00:39:22]

In one or two days. This is much quicker than installing a heat pump, which typically takes over five days. It means our product can be a quick replacement option, even for emergency situations.

Liz Allan [00:39:59]

Brilliant! So, what's the lifetime of the Tepeo ZEB?

Johan du Plessis [00:41:14]

We offer a 10-year guarantee but expect it to last over 20 years. It’s designed to be durable, with some replaceable components that can be serviced. The thermal storage technology doesn't degrade, which is a significant advantage.

Liz Allan [00:41:56]

That's fantastic. I really hope this innovation gets the support it needs. Thank you so much, Johan, for sharing all this valuable information.

Johan du Plessis [00:43:37]

Thanks, Liz. We’re excited about the future, and it's great to see industry and policymakers starting to support innovation. 

Liz Allan [00:44:05]

I’ll have to come over to Winnersh and see it in person!

Johan du Plessis [00:44:14]

Please do. It's our home, where all our R&D happens, and we manufacture our products. We'd love to show you around.

Liz Allan [00:44:26]

Thank you again, Johan. And to everyone else, thank you for listening and watching. We'll see you next time. Bye!