Energy storage systems

Abstract

There is herein described energy storage systems. More particularly, there is herein described thermal energy storage systems and use of energy storable material such as phase change material in the provision of heating and/or cooling systems in, for example, domestic dwellings.

Description

FIELD OF THE INVENTION[0001]This invention relates to energy storage systems. More particularly, the present invention relates to thermal energy storage systems and use of energy storable material such as phase change material in the provision of heating and / or cooling systems in, for example, domestic dwellings.BACKGROUND OF THE INVENTION[0002]Although there are many heating and cooling systems on the market many of these prior art systems suffer from efficiency problems and are also expensive to run. Prior art systems also tend to be based on fossil fuels which are environmentally unfriendly.[0003]Space heating (“heat”) and hot water are an expected facility in homes, offices, factories, hotels, shops, etc around the world. Recent common practice has been to deliver this type of heating on-demand by burning storable energy sources (e.g. oil, gas and the like) or by using electrical energy (typically generated from gas or coal) in a heating element.[0004]In most cities in the world...

AI Technical Summary

Benefits of technology

[0214]One or more banks of a thermal energy store may be used to store excess and / or waste heat from a cooling system during the daytime (and / or any other period of peak heat load) so that the heat can be dumped at a later time selected such that any required additional pumping and / or heat pumping energy will have a lower cost and / or be more available, for example but not limited to, when a lower costs night-time tariff from an electric utility is in force and / or when the wind blows on a wind turbine to generate electrical and / or mechanical power.

[0215]Any heat pumping and / or pumping of thermal energy between banks and / or to / from banks and thermal energy sinks / sources may be, in at least some cases and / or on at least some occasions, made to occur at a time selected such that any required additional pumping and / or heat pumping and / or heating and / or cooling energy will have a lower cost and / or be more available, for example but not limited to, when a lower costs night-time tariff from an electric utility is in force and / or when the wind blows on a wind turbine and / or the sun shines on a photovoltaic panel to generate electrical and / or mechanical power.

[0216]Any heat pumping and / or pumping of thermal energy between banks and / or to / from banks and thermal energy sinks / sources may be, in at least some cases and / or on at least some occasions, selected to occur when the temperatures of the banks and / or the thermal energy sinks / sources are such as to make the temperature difference between the source and destination of each thermal energy transfer optimal and / or preferable and / or better than at other times (whether on the basis of historical record and / or predicted future performance), so as to reduce the use of additional pumping and / or heat pumping and / or heating and / or cooling energy.

Problems solved by technology

Although there are many heating and cooling systems on the market many of these prior art systems suffer from efficiency problems and are also expensive to run.

Prior art systems also tend to be based on fossil fuels which are environmentally unfriendly.

So going back to the original fuel, electric heating is only around 30% efficient.

As a result we face major problems in continuing to use these fossil fuels:

The consequence is climate change with potentially catastrophic consequences in loss of both planetary biodiversity and human habitat (water shortages, desertification, and sea level rise).

They are therefore only really suited to generating grid electricity.

Except in very few parts of the world, hydro cannot provide the bulk of the demand for grid electricity.

There are limited further sites to implement large reservoirs, and there can be human and bio-diversity issues around flooding large areas.

However there are major concerns about competition between food and bio-fuel crop production, and between bio-fuel crops and naturally bio-diverse land (e.g. the elimination of jungle for palm oil).

It can be observed that apart from biofuels and some hydro, solar-driven renewables energy conversion devices do not operate on-demand (or in the jargon of the electricity generating industry, they are not “dispatchable”): their energy comes when the sun shines; when the wind blows; when seas are high.

Storing electrical energy is difficult.

This process is 90% efficient, but suitable pumped-storage hydro sites are scarce.

The liquid-gas phase change material is usually not practical for use as thermal storage due to the large volumes or high pressures required to store the materials when in their gas phase.

However, there are a number of problems with practical use of phase change materials including achieving suitable rates of heat transfer in and out and acceptable levels of thermodynamic efficiency.

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