Solar energy though abundantly available, has rarely seen as a useful form of energy till recently. Sun being the focal point of all life forms and natural phenomena on earth, became a trusted source for almost all energy requirements by efficiently trapping and converting to useful applications. Solar radiation consists of various energy forms such as light and heat radiations over a large spectrum of wavelengths. The sunrays are an abundant source of energy, if tapped properly can solve almost all the energy requirement of man today.
 
Solar Energy can be classified into two categories, solar thermal and solar light. Photovoltaic cells (PV) use semiconductor-based technology to convert light energy directly into an electric current that can either be used immediately, or stored in a battery, for later use. PV panels are now becoming widely used, as they are very versatile, and can be easily mounted on buildings and other structures. They can provide a clean, renewable energy source, which can supplement and thus minimize the use of electricity supply. In regions without main electricity supply such as remote communities, PV energy can provide a reliable supply of electricity. The disadvantage of PV panels is their high cost and relatively low energy conversion rate (only 13-15%). Thermal solar on the other hand has average efficiency levels 4-5 times that of PV, and is therefore much cheaper per unit of energy produced. But in the near future PV panels can be manufactured at much cheaper price. This will create an explosive growth in the solar market as third world countries find extensive use of PV. Thermal energy can be used to passively heat buildings through the use of certain building materials and architectural design, or used directly to heat water for household use. In many regions, solar water heaters are now a viable supplement or alternative to electric or gas hot water production.
 
Thermal energy obtained from the sun can be used for a number of applications including producing hot water, space heating and even cooling
 
Using solar and other forms of renewable energy reduces reliance on fossil fuels for energy production, thus directly reducing CO2 emissions. CO2 emissions contribute to global warming, an environmental issue which is now of great concern. The average household can reduce green house gas emissions by as much as 20% by installing solar water heater. Current estimates show that by installing one domestic solar water heater of 100LPD saves 1.5 tones of CO2 annually.
 
Solar water heaters offer shorter payback period compared to yesteryears. To day a 2-year payback period sounds very common.

Burning fossil fuels such as coal for electricity production, and gas for water heating both release large amounts of CO2 into the atmosphere contributing to green house effect which is the main cause for the much talked about global warming. By using renewable energy sources such a Solar Thermal, Solar PV, Wind, Hydro and Geothermal, reliance on fossil fuels can be minimized, thus directly reducing CO2 emissions.

On average for every 1kWh of energy produced by a coal power station, 1kg of CO2 is produced. Burning natural gas for electricity production or water heating produces about 450grams of CO2 for every kWh of energy produced.

In the average household, water heating accounts for around 30% of CO2 emissions. By installing a solar water heater, which can provide between 80-100% of your hot water heating energy needs, you can reduce your total CO2 emissions by more than 20%.

The following graph shows the conservative estimate of CO2 emissions by various forms of heating medias and its production.
 
CO² emissions from heating systems producin3,500 kWh/a (meets the warm water needs of a four to five person household) and with a solar coverage percentage of 65%
 
Basics of solar water heater

Solar insolation
Amount of electromagnetic energy (solar radiation) incident on the surface of the earth.
Knowing the region’s insolation levels, one can more accurately design the system. The collector size/ number is dependent on the insolation level.

Units of Insolation levels
The values are generally expressed in kWh/m2/day. This is the amount of solar energy that strikes square meters of the earth's surface in a single day.
The unit conversions are

1 kWh/m2/day = 317.1 btu/ft2/day = 3.6MJ/m2/day

1kWh = 3412 Btu = 3.6MJ = 859.8kcal

Every region has its own insolation levels, which varies over the seasons. A typical higher and lower insolation levels are:


Central Australia = 5.89 kWh/m2/day - Very High
Helsinki, Finland = 2.41 kWh/m2/day - Very Low

When determining what size collector you need, you must consider two key factors: solar radiation level and energy requirements. Energy requirement will usually take into consideration the volume of water and rise in temperature required. Normally HYKON collectors are designed for either100/125 LPD systems. If you require higher temperatures or higher systems, a suitable system selection is required. The selection is based on economic considerations, hot water consumption pattern etc.

It is equally important to design systems to the actual requirement than over-designing which causes the system to over heat and energy losses by leakage and parts damages. Normally an 80-90% of the peak demand of hot water is considered for design purpose, which will suffice for family’s requirement on an average

While designing the system, if we got a design that is non-standard, as a general rule, select the next size down - this will prevent having too much heat in the system.


To calculate the heater requirements one must know the main factors that determine the type of system required.

These factors are

1.Insolation level

2. Quantity of water

3.temperature rise. Temperature Rise = target hot water temp - average mains cold water temp.
Target hot water temp should usually be around 55-60oC
when showering water temp is approximately 400C

4. Shade pattern

5. Angle system installation

6. Installation site (Do you have enough room for the collectors?)

The above directions are only for a guideline and should not consider for a detailed system design. HYKON installation engineers are available for assisting the customer in selecting designing and selecting a suitable solar water heating system. You may contact any of the HYKON branch office or approved dealers/distributors.

The key purpose for product certification is to ensure the consumer is receiving a good quality product, that not only provides good performance, but that is safe, and will provide years of reliable use. HYKON systems are ISI approved and manufactured under ISO 9001 quality environment.


Worldwide capacity of solar thermal energy -an estimate

10 November 2004. The International Energy Agency's Solar Heating and Cooling Programme and major solar thermal trade associations publish new statistics on the use of solar thermal energy. The new data - expressed for the first time in GWth, rather than in square meters of installed collector area - shows the global installed capacity to be 70 GWth (70.000 MWth).

 
 
"The worldwide contribution of solar thermal installations to meeting the thermal energy demand for applications such as hot water or space heating has been greatly underestimated in the past", says Michael Rantil, Chairman of the International Energy Agency's Solar Heating and Cooling Programme (IEA SHC), "With an installed capacity of 70 GWth solar thermal is one of the leading sources of renewable energy world wide. And its potential is much, much higher."
 
Hykon Evacuated Glass Tube / Glass Glazing solar heaters

1. Solar water heating reduces the monthly operating expense of the household.

2. Gives flexibility and increased purchase power.

3. Solar water heaters are the only home appliances that save money without compromising quality of life.

4. Solar water heating is a protection against predicted increase in energy cost in the future.

5. Reduce dependence on import of oil and the need to build expensive new power plants.

6. Solar is environmentally safe, conserves resources and reduces air pollution which causes acid rain, the ``Greenhouse Effect" and respiratory health problems.

7. The Hykon solar water heater has no moving parts to fail or maintain.

8. The unit doubles the hot water supply of the house when added to an existing water heater (optional)

9. The Hykon SWH unit comes with a minimum design life of 20 years.

10. Solar Energy is technology that contains the cost of the fuel in the initial price of the equipment.

11. Can be used as a stand-alone heater; great for remote areas or where no electricity is available for heating water.

12. Can be installed on almost any house as a retrofit, connecting to the existing water heater.

13. Can be installed on the roof or the ground.
 
 
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