The Internet of Tanks

The CEO and co-founder of Mixergy discusses his company’s new partnership with Centrica

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With unprecedented levels of renewable power in the UK, and tough decarbonisation targets ahead, Mixergy, a clean-tech spin-out from the University of Oxford, has received investment from Centrica as part of a significant partnership that will see the roll-out of smart hot water tanks. Centrica, which owns British Gas, will provide thousands of customers with the opportunity to have an Internet of Things-enabled, smart hot water tank as part of an upgrade of their existing system. This will create huge energy surplus potential and as a result, greater flexibility to support the National Grid.

The tech behind the tank.

The Mixergy tank is a smart product with a difference. The tank heats efficiently when there is surplus renewable energy. It does this in two ways. First, a novel arrangement floats hot water on cold by exploiting thermal stratification; this allows the tank to only heat the amount of water required, reducing energy consumption while providing more headroom for surplus renewables.

Second, a sensor measures the level of hot water in the system, allowing the user to see how much hot water there is while eliminating the possibility of having to endure a cold shower. The same technology enables the tank to decide when to heat and whether to use gas or electricity depending on real-time prices in the energy market. Energy consumption is reduced by more than 10 per cent, reducing energy bills while British Gas is able to assist the power sector to absorb low-carbon electricity.

In September, Mixergy became the first domestic hot water product certified by the National Grid to provide grid flexibility services – an important first step in realising its Internet of Tanks vision to decarbonise the energy networks and become the UKs biggest virtual battery.

The technology has been developed in response to two key trends:

The transition from fossil fuels

The UK’s electricity system has been transformed over the past decade. For the first time since the 1800s, coal power stations have idled on days where renewables have taken up the demand.

Overall, coal power production plummeted from 20 per cent to 5 per cent in the last seven years as the cost of off-shore wind has been slashed by two-thirds over the same period. In the last three months, renewable power production has surpassed all fossil fuels for the first time in the history of the power grid. This means that for each unit of electricity consumed, CO2 emissions have fallen considerably. In July, levels dipped below 100 grams of CO2/kWh, 45 per cent lower than the equivalent carbon intensity associated with burning natural gas.

Increasing demand for energy storage

In March, a combination of strong sunshine and low demand culminated in an oversupply of electricity for six hours. If electricity production rises too far above demand, voltages rise while power stations speed up to dangerous levels. In response, electricity markets encourage industry to consume energy and prevent the system becoming unstable. These events are leading to growing demands for energy storage
to soak up excess energy when it is cheap, and to deliver it back to the grid when power would otherwise have to be generated using fossil fuels.

For more information, please visit: www.mixergy.co.uk