Solar water heating

The complete solar solution

What is solar thermal?
A solar thermal system typically consists of the solar collector(s), a pump, and a twin coil hot water cylinder which acts as a thermal store. Solar water heating (known as solar thermal) systems capture the free heat from the sun and use it to heat up water for use in the home. It’s a simple process:

A conventional boiler or immersion heater can be used to make the water hotter, or to provide hot water when solar energy is unavailable.

  • panels on your roof absorb heat from the sun – they are known as the collector
  • the water in the panels heats up, this hot water is pumped through a coil in your cylinder, which transfers the heat to the water in the cylinder
  • If the cylinder’s temperature sensor detects that the solar panel has not collected enough energy to heat the water to its pre-set temperature, it allows the main heat source to top it up (i.e. a boiler). The control panel can be set to optimise efficient use of the solar panel and ensure hot water is available at the times you need it.

Evacuated tubes are aligned in parallel; the angle of mounting depends upon the latitude of your location. As a rule of thumb you need between 1 and 2 m2 of collector (solar panels) per person living in the house. Shade on the panels at any time of day will reduce the performance. The key element determine that the performance of tube is the technology of the film coating, and it is the best efficient tube you can find in London, with the highest absorption rate of near 93% comparing with common rate of 90% and lowest emission rate about 4% comparing with common rate of 7%.

Most panels are mounted on a roof, but they can also be mounted at ground level. It is important that they get direct sunlight. To get the best results they should be at an angle between 20 and 50 degrees from horizontal.


Solar Thermal serving Ealing, Islington & the London Area

What type of solar thermal panel is best?

Solar panels are compatible with most existing hot water systems. However, you will need a new cylinder with two coils. Ideally it should be big enough to hold two days worth of hot water.

Solar thermal panels should provide most of your hot water from April to September, and make a worthwhile contribution in the months on either side of that period.

Solar water heating panels in their simplest form are made from a sheet of metal painted black which absorbs the suns energy. Water is fed through the panel in pipes attached to the metal sheet and it picks up the heat in the metal. For the UK climate, the pipework contains non-toxic anti-freeze. The pipes are often made of copper for better conduction. The metal sheet is embedded in an insulated box and covered with glass or clear plastic on the front. The system is usually installed on the roof.

A correctly sized solar thermal system will provide around 70% of annual domestic hot water demand and can assist underfloor heating and swimming pools if specified for this demand.

Just like an automobile engine, the computer CPU, evacuated tube is core of the solar water heater.
Its similar to a conventional Dewar flask and consists of two borosilicate glass tubes, resisting to high chemical and thermal shock. The outer side of the inner tube is coated with a sputtered solar selective surface. This coated inner tube is closed at one end and sealed at the other end to the outer tube. The annular space between the outer tube and inner tube is evacuated to avoid heat loss in conduction and conversion.

The Benefits of Solar Thermal

  • Free hot water- Solar thermal works all year round, though you will need to heat the water further with a boiler or immersion heater during the winter months.
  • Lower your carbon footprint- Solar hot water is a green, renewable heating system and can reduce your carbon dioxide emissions.

Sunlight is free, so once you’ve paid for the initial installation your hot water costs will be reduced and you will be protected against future price rises.

Renewable energy for existing homes

Increasingly householders are coming to understand the financial and environmental benefits of integrating renewable energy technologies within their homes.

Are there any requirements before having an installation?

An old or single coil hot water cylinder will need to be replaced with a twin coil cylinder. A&C Heating and Plumbing can identify and provide all kinds of heating upgrades necessary for the installation of a solar thermal system, and can supply these as part of an installation package.

Please do request a free, no obligation site survey to find out how a solar thermal system could be integrated into your existing heating system. Call us now for a free fast response on 08001777957