Thermochemical energy storage using a closed cycle (ThermoStore)

As part of its effort to commit essentially net zero carbon emissions by 2050, the UK Government announced a new plan in March 2019 to ban gas boilers in new houses after 2025. This is based on a fact that residential buildings accounted for about 25% of total UK greenhouse gas emissions in 2012, of which 55% were directly from gas, according to the Committee on Climate Change. The Committee advised direct emission reductions of 36% by 2025 and 53% by 2030 from 2007 levels in buildings. This has led to an imminent demand for replacement low or zero carbon heating technologies.
Solar thermal technology appears a primary option to meet this demand, but possesses a common drawback, that is the temporal mismatch between solar heat production and heating demand in buildings. Seasonal storage of solar heat is an essential way to address the mismatch between heating demand in winter and solar heat production in summer. Of the three main technologies available, energy density of thermochemical energy storage is superior to conventional sensible and latent heat storage by several-fold factor and has a further advantage of negligible storage heat loss.
The proposed project is aimed to investigate a new solar driven thermochemical energy storage system using several innovative designs such as closed air loop, pressure control, embedded internal heating/cooling, hollow polymer fibre heat exchanger, and integrated dehumidification/evaporative cooling. The proposed system has been devised to address several drawbacks experienced by typical thermochemical energy storage systems and will also use low temperature solar heat to enhance the heat release discharging process by humidifying air flow at a slightly higher temperature. The project is built on our recent research on the design and fabrication of composite salt-in-matrix as thermochemical energy storage materials.
Development of the proposed system has the potential of reducing fossil energy usage in space heating and hot water. Implementation of such technology would allow the UK to greatly increase its utilisation of solar energy and achieve the target of decarbonisation in heating. This project will demonstrate to domestic consumers, house builders, industry and local authorities the practicality of heating buildings by renewable energy without increasing costs. The project will also provide an opportunity for UK industries to pioneer the development of a new advanced solar heat storage technology.

The proposed project is likely to produce a beneficial impact to the nation, industries, society and customers. This is specifically described as below.
There needs a significant improvement in energy storage technologies during next decades to contribute to the Government target of net zero carbon emissions by 2050. The proposed project will develop a new-type solar driven thermochemical energy storage system by investigating use of several innovative designs, in order to address some drawbacks experienced by typical thermochemical energy storage systems. Seasonal storage of solar heat is an essential way to address the mismatch between heating demand in winter and solar heat production in summer. This has been identified worldwide a promising 100% renewable energy solution for space heating and hot water in buildings. The innovative outcome from this project will enhance UK scientific excellence in seasonal energy storage.
The project is expected to produce some exploitable outcomes and provide a scientific foundation for UK industries to pioneer advanced thermochemical energy storage technologies and hence promote their competitiveness in market. The supporting industrial partners will get a direct experience through different stages of project by providing a technical support at the same time, which can set a good background for a fast exploitation. Commercialisation of the proposed technology will create job opportunities and encourage "green" economic development in the UK through the manufacturing of the system components notably thermochemical reactors, solar collectors and heat exchangers. The follow-on development of other applications of the thermal storage will create very large worldwide markets for the UK.
The project will demonstrate to domestic consumers, house builders, industry and local authorities the potential for the proposed system in the reduction of their heating costs, and hence improving their living standard. The expected key features, i.e., low cost, high efficiency, low maintenance, ease of production, will stimulate the market uptake for the proposed system by offering a renewable energy heating solution the sustainable development of the UK economy. The project dissemination activities will also help more broadly in enhancing public awareness that energy savings and reduction in GHG emissions is possible if technologies are properly developed.
The project will have a technical support from 3 industrial collaborators (EPS Ltd., Solar Ready Ltd., SG Biodrying Ltd.). The collaboration will encourage knowledge transfer between academia and industry based on the development and demonstration of the proposed novel technology. The project partners have the necessary skills/resources to fully deliver the identified tasks. The academic Applicants will benefit in terms of improved research collaboration profile and exposure to the commercialisation atmosphere. The project will provide an opportunity for the companies to advance their manufacturing capability in supporting this state-of-the-art development, so the companies can be prepared well in exploring additional aspects of the concept and into other UK sustainable energy projects.