Why are Thermal Stores so important?

Why are Thermal Stores, Accumulators and Thermal Stores  so important?

What happens if I don’t have one?

Because the way many renewable heating systems work, eg wood, solar, heat pumps etc there is not a instant heat created, heat takes time to be created.  A  log / pellet / chip boiler does not simply create kw’s of energy instantaneously it takes time to get going unlike gas and oil boilers which are virtually instantaneous.    In a similar way solar heated tanks rely on the sun to charge them, however in the uk we cant guarantee when the sun may come out.  This is where hot water storage systems come in, they ensure you have heat when you need it

Domestic hot water, coils, tank in a tank, and heat exchanger

Thermal stores can produce DHW (hot water to the taps) this can vary in its method, depending on quality needed and the thermal store budget there are 3 main methods.

1. A dhw coil, this is a coil made of copper or stainless steel, and is as the name suggests a coil.  The coil enters the tank normally near the mid point and exits at the top.  Mains pressure water (normally reduced to the manufacturers specification) enters the coil at the bottom and exits the coil at the top as hot water, the cold water is simply heated by the surrounding hot central heating water, the coil ensures no mixing of water.  As the now hot dhw leaves the tank it is blended to a safe temperature normally around 40’c .   This type of arrangement has minimal moving parts and will work in power failure.  For this system to work well you need to have the manufacturers recommend  water pressure around 3 bar with around 12 liters a minute of water available.  However we have seen them work well on 1 bar, there is also a array of mains water pumps on the market to boost the pressure if needed.
2. Tank in a tank, all our large tanks above 4000 litres have tank in a tank dhw, please see the picture below.  Tank in a tank is as the name suggests, a tank suspended within another tank, the central heating water simply heats the dhw in the stainless steel tank. The dhw tank is stainless steel and is of a certain size to accommodate the propertys dhw needs, tanks are sized to accommodate your needs and in multiple property occupancy ( flats) multiple stainless steel tanks can be added to the thermal storage tank, so every property has its own dhw tank, this is only generally used where large seasonal solar hot water tanks are used. Please see solar seasonal storage tanks for information (in solar thermal pages)
3. dhw heat exchangers. Gondwana Green Heat has never had a love afair with this form of producing dhw. It works by having a plate heat exchange outside the tank, a flow and return pipework from the tank to the heat exchanger and a cold water in and hot water out arrangement. Please see the picture below to better understand this option.  The flow rate is dependent on the quality and type of heat exchanger, this form of dhw creation does not function in power failure, but is a very cost effective solution for budget thermal stores

system link ups different technologies heating the same space

Thermal storage systems also have the benefit of allowing us heat a property with a arrangement of heating technologies, for example Gondwana Green Heat does lots of wood burning boiler stoves many people want to link this to there existing gas or oil central heating. This is easily done with a small thermal store, e.g. 210 250 liter thermal store. Both heat sources are plumbed into the thermal storage tank, allowing the wood burning boiler stove to heat the tank when its in use, all other periods the gas or oil central heating boiler satisfy’s the thermal storage system.

The options are endless for thermal storage systems and there configurations, we could write a book on it easily, however I’m not sure it would be a best seller.

Gondwana Green Heat retails, imports and designs are vast array of hot water systems for our own projects as well as the general public, industry professionals and the trade.  If you need help with a project please don’t hesitate to get in touch, we now also sell a range of thermal storage tanks in our web shop.  Please have a look.