Caldera has developed a Zero Carbon Boiler (ZCB) which takes renewable electricity from the grid and converts it into heat which is stored within the unit until the consumer wants heating or hot water. The ZCB has an innovative core inside that is trademarked as "Warmstone" Technology. The Warmstone technology is a low cost storage media that is able to absorb renewable electricity and store the equivalent energy for a four bedroom home to cover a 24 hour period on the coldest winter day or seven days of hot water in the summer. The energy is retained with 5-10% losses per day with an efficient insulation strategy. These thermal losses are over 5x lower than conventional methods of storing heat, such as night storage heaters. This project is about unlocking the full potential of the ZCB for Heat as a Service (HaaS) by: 1. Developing the communications so that the timing and rate of electrical charging can be set and varied on a minute by minute basis by an energy supply company, 2. Collecting heat usage data from the Heat Interface Unit (which replaces the conventional boiler), so that the homeowner can be charged just for the heat that they use rather than the electricity supplied to the ZCB 3. Working with large social housing landlords to establish initial trial sites, which will lead to 5+ installations in 2021 and can be used to demonstrate that rapid wide scale deployment is possible. Supply side companies are currently developing software to actively control demand in the home and smarter ways to use energy by changing consumer behaviour. The Caldera Warmstone approach provides a means for storing electricity for heating. Heating is the largest home energy demand - normally 4x the rest of the homeowner's electricity usage. The HaaS model will help low income individuals and families who will benefit the most from reduced energy costs by showing that a ZCB can be supplied and installed under a long term finance model. The HaaS model has been trialed in a number of countries with heat pumps or conventional boilers, but not with a ZCB that is able to decouple electrical charging and heat supply by 1 to 7 days depending upon the time of year. This means that the unit can be charged when renewables are generating and the electricity price is lowest. Heat pumps work in real time and although they generate "additional free heat" they also have to operate when the consumer wants the heat or hot water, not when renewables are generating. Low or zero carbon heating systems with lower cost of ownership normally have high upfront capital costs that make them inaccessible to those that have the most need for savings. To eliminate this initial capital outlay, the unit can be financed by a third party and the cost to the user spread over the expected 20 year life.

Caldera is a heat storage company looking to decarbonise the economy by solving grid scale problems. The UK government is looking to tackle the economic impact of Covid-19 by 'building back better' a green economy that will deliver directly on the government's Clean Growth Strategy and net zero carbon ambition. Caldera has developed a Zero Carbon Boiler which takes renewable electricity from the grid and converts it into heat which is stored within the unit until the consumer wants heating or hot water. The Warmstone technology will increase the amount of renewable energy that can be productively used, which in turn keeps down the cost of renewable energy. To bring this technology a step closer to reality, the unit needs to be developed to a point where it is safe to deploy and test in a domestic home. The Zero Carbon Boiler has an innovative core inside that is trademarked as "Warmstone" Technology. The Warmstone technology is a low cost storage media that is able to absorb renewable electricity and store the equivalent energy for a 4 bedroom home to cover a 24 hour period on the coldest winter day or seven days of hot water in the summer. The energy is retained with 5-10% losses per day with an efficient insulation strategy. The Zero Carbon Boiler is cylindrical in shape, weighs 1.5 tonnes and is 1m in diameter by 1.6m tall. The unit will be located externally to the property or in a garage or plant room. The existing boiler is removed and replaced with a Heat Interface Unit. Heat Interface Units are mass produced as they are used in district heating networks to transfer heat from the network to individual homes. The use of a standard Heat Interface Unit means that this technology is a straight forward retrofit and can be carried out by a plumber without additional training or modification to the property. The Heat Interface Unit is connected to the Zero Carbon Boiler via two insulated pipes. The Zero Carbon Boiler is also connected to the main electricity supply to the home. To date a half size unit has been built and tested in Cadera's production facility in Fareham, with a full size unit in manufacture ready for deployment to a test house in September this year (2020). When the new unit has been installed and is functioning in the test house it will be at Technology Readiness Level 5 (September 2020). This project will develop the Technology Readiness Level 5 unit to a Technology Readiness Level 6 status so that it can be safely fitted in real homes in summer 2021 for trials over the following winter. The project will include the manufacture of two units with one being used for certification testing and the other installed for trials at the Caldera facility in Fareham.

"Half a billion people could be pushed into poverty as economies around the world shrink because of the coronavirus outbreak, a new study has warned. Poverty levels in developing countries could be set back by up to 30 years, research released by the United Nations University's World Institute for Development Economics Research." 9th April 2020 Almost 3.7 billion people in the world use biomass for cooking, which creates a burden that includes health hazards (respiratory illnesses and burns), increased deforestation, spending a large proportion of income on fuel, time spent collecting fuels, and reduced educational opportunities for women and girls. For decades the dominant policy on cooking energy has been to improve the combustion efficiency of biomass fuels. This policy has broadly failed and the dispersal of improved cookstoves is not keeping up with population growth. Proposals have been made for alternative approaches using electrical cooking either from batteries + solar PV (e-cook) or from electrically powered low energy pressure cookers. The first of these has proved too expensive and the second is culturally difficult involving changes to people's established cooking patterns. The project will explore a third option by building and testing a low carbon, low cost, secure cooking energy solution, which uses a vacuum insulated heat storage block charged from solar PV. Pumped Heat, a UK SME, have developed and patented a game changing thermal storage material that has multiple applications worldwide. This project will help to protect and create UK jobs and world class expertise in the rapidly growing field of energy storage. It will also support the UK's leading role in development of a clean cooking solution for the world. The original project has allowed us to build and test an insulated clean cooker that has hit all of the technical targets needed in terms of cooking power, insulation losses, and energy stored. This first cooker is being tested by a partner organisation in Kenya. The extension to this project will allow the build and testing of five further cookers. Two cookers will be tested in Kenya by a for-profit social enterprise that promotes a wide range of cleaner cooking solutions. The remaining three units will remain in the UK for more structured and technical testing of performance and demonstration to philanthropic investors..