Sun Harvester - Information

Solar Water Heating Systems - Funding Banner

Sun Harvester - Why Solar Hot Water Systems?

Solar Water Heating Systems - Thermometer graphic

The world is using up fossil fuels like gas, oil and coal at an ever-increasing rate and with alarming consequences. We are, however, provided with an abundance of energy, renewed daily, which we can easily tap into without harming our precious environment.

The actual amount of useful energy provided will depend on:

Climate (the amount of solar radiation & air temp)
The solar collectors (sizing, efficiency & position)
Hot water usage (amount, temperature & pattern of us

For a household of four persons, we would suggest 4 square metres of panels from which the useful energy contribution provided is likely to be in the region of 2,600 KWh per year. This would provide on average 50 - 60% of the household's annual hot water requirements. This would also reduce C02 emissions by over one tonne per year.

Solar Water Heating Systems - System Flow Graphic

Solar Water Heating Systems - Solar Energy Avaliblity Graphic

Solar energy availability in the UK is much greater than most people imagine. Indeed the UK receives on average about 65% of the annual radiation experienced by the south of Spain. The solar energy that we experience is accounted for by approximately 40% direct radiation (received when it is sunny), and 60% diffuse, or scattered radiation (received on cloudy days). Whilst the highest amounts of monthly solar radiation are obviously experienced in the summer months, there is enough radiation in Spring, Autumn and Winter to make a useful contribution to a household's energy needs:

80- 90% of all Summer hot water needs
40-50% of Spring and Autumn requirements
20 - 30% of Winter water heating needs

The main types of solar collectors are:

Flat plate collectors without selective surface (usually painted black)
Flat plate collectors with selective surface
Evaculated tube solar panels

Sunharvester solar panels fall within category 2. They have a selective surface, which increases the efficiency of a solar collector as it is effective at absorbing solar energy but does not radiate the heat. A black painted panel would, for example, at 60ºC radiate back as much energy as it is collecting. The panel however, with its special selective surface, only loses 12% through radiation losses at l00ºC.

The Solar Energy reaching the Earth is 30 million times the total energy requirement of mankind