Mixergy paves the way for a smarter, sustainable energy future

With this innovative concept in place, Oxford University Innovation (OUI) played a pivotal role in Mixergy’s evolution from a groundbreaking research project within the university’s Department of Engineering Science to a market-leading provider of smart hot water storage solutions. Originating from the research of the Energy and Power Group, Mixergy showcases the transformative potential of university spin-outs in tackling global challenges like climate change and energy security.

As the Labour government commits to quadrupling offshore wind capacity and tripling solar energy by 2030, maintaining grid stability will become increasingly challenging. To help meet these demands, GB Energy, a publicly owned clean power company, has been tasked with increasing renewable energy generation. However, experts believe the current grid infrastructure may not be sufficient to manage the expected surge in energy from new wind farms and solar installations.

Between January and October 2023, Carbon Tracker estimated that the National Grid paid £590m in curtailment payments to wind farms, compensating them for shutting down during periods of excess generation. This cost consumers an average of £40 per year. Flexible, grid-connected technologies offer a promising solution, helping to reduce the need for costly and controversial large scale infrastructure upgrades.

Mixergy has emerged as a leader in this space with its smart, grid-connected hot water storage solutions. By storing energy when renewable power is plentiful, its cylinders help relieve grid pressure during peak times. By heating only the required amount of water, Mixergy’s technology not only optimises energy use within homes but also creates additional capacity for renewable energy sources such as wind and solar farms to operate more efficiently.

Through its partnership with British Gas, Mixergy launched a first-of-its-kind energy offer: Mixergy eXtra. This initiative has the potential to benefit millions of homeowners with hot water cylinders, helping support the grid while reducing energy bills. The scheme offers users of its smart hot water cylinders an annual award of £40 when they sign up for a British Gas energy tariff. This marks the first time a utility has offered financial incentives to homes adopting a grid-connected hot water solution.

Alumnus Pete Armstrong, CEO and co-founder of Mixergy, said: “The idea of paying homeowners to use surplus renewables in their cylinder is an industry first. We know our grid will need flexible demand to accommodate the huge surpluses of renewable generation that will arise soon. The concept of a smart hot water cylinder was born from our work within the University of Oxford back in 2014, and it’s incredible to see how much renewable energy capacity has grown since then. We’re thrilled that British Gas is the first utility to offer Mixergy eXtra, helping address this growing challenge. Why pay wind farms to shut down when we can incentivise homeowners to use more renewable energy?”

Andy Robertson, Deputy Head of Licensing and Ventures at OUI said: “As homes switch to electric heating, hot water storage will be key. Mixergy offers an ideal solution, combining efficiency, sustainability, and ease of use to meet the demands of the modern energy grid.”

He added: “It’s amazing how Mixergy anticipated the challenges the UK would face with the transition to renewables. The first time we saw their idea – which they then called Aqualibrium – the whole idea of using heating water to help balance the excess renewable energy was already thought through. Of course getting from that initial idea through business and product development to deliver Mixergy eXtra has been a brilliant example of what Oxford students and Oxford spinouts can do to deliver impact from their research and societal benefit.”