- Did you know that in the domestic sector the hot water use reuires the most energy inside the household?
- Why Choose Solar Energy?
- Why Use Solar Technology?
- What are the Benefits to Users?
- What is a SOLAR WATER HEATER?
- What is it composed of?
- What are the two majors factors affecting the performance of a properly installed SWH system?
- How much can a household save by investing in a solar water heater?
Did you know that in the domestic sector the hot water use reuires the most energy inside the household?
The electric water heater represents approximately 40% of the electricity bill of a standard household.
Harnessing the power of the sun may ultimately prove the best way to sustain economic and social growth without damaging the environment. Concerns about climate change, together with the need to secure energy supplies for the future, mean that the energy chain must become progressively decarbonised as we move forward into the 21st century. In a world which is still dominated by fossil fuels, more and more people are not only demanding access to energy, but also asking for clean energy. Solar thermal power systems are able to meet those individual demands for a safe, reliable and clean form of energy all over the world.
Consumers using solar thermal energy contribute to the rescue of the environment by choosing clean energy, and ensure remarkable cost saving on their daily energy consumption as well as an increasing independence from their power utility supplier. Renewable energy now provides an increasing proportion of the world’s energy demand. Nevertheless, the continuous growth of renewable energy encounters some great restrictions. Why? Because many renewable energy forms are still commercially unproven and expensive if compared to traditional fuels. Government support is needed to make them a priority, but this is not enough.
The sun constitutes one of the important energy sources, if not the most significant of all. Ever since man discovered its unique properties, he found various ways to use it in order to improve his standards of living.
Energy Security: More than half of the world’s conventional oil reserves are concentrated in the Middle East. With the IEA Member countries depending on foreign sources for the majority of its oil needs, energy security is not only a matter of scarcity, but regional distribution and relations between the export and import countries. Solar energy is the most abundant and widely distributed renewable energy resource in the world, and yet the potential of this “local” energy source—produced close to where it is needed—has hardly been tapped.
Environment: Managing the interaction between energy use and the environment remains a major challenge for policy-makers today. Carbon dioxide from fossil fuel combustion alone creates roughly four-fifths of the total man-made greenhouse gas emissions. Solar energy displaces carbon-emitting sources while providing a non-polluting energy source for heating and cooling.
Economic Growth: Investments made in solar thermal technologies create jobs in many different sectors from research and manufacturing, to the service industry (e.g., installers and distributors).
What are the Benefits to Users?
Increasing gas and oil prices mean higher utility bills. With no decrease in costs insight, consumers are tied to this volatile market. Solar technologies in homes can lower the use of non-renewable energy sources for space and water heating by a factor of three. In offices, daylighting applications alone can reduce electric lighting use by 30% – 50% as well as improve worker performance.
It is a device which utilises solar energy in order to produce domestic hot water for FREE!!
In simple terms, a hot water storage tank and a collector.
What are the main advantages of solar panels (flat plate) over evacuated (vacuum) tubes? Why are the more suitable for domestic use in Malta?
Flate plate collectors in Malta and around the Mediterranean region are by far more suitable for domestic use than the evacuated tubes. Well over 90% of the solar water heater systems installed in similar climatic conditions to those in Malta use solar panels. This is mainly due to the generation of excessive temperatures, unnecessary wasted heat and the formation of scale, resulting in high maintenance.
In summer, vacuum tubes keeps generating hot water at times even in excess of 1000C, causing several problems. The boiler of the system itself may not withstand such high temperature and pressure, which could develop into the boiler leaking. Furthermore, this highly elevated temperature and pressure may also result in severe problems in the plumbing itself, which may serious damage and more serious water leaks in the piping system throughout the house.
Also, it is highly important that the solar water heater is sized suitably by experienced professionals by carefully assessing the demand of hot water in the household, by taking into consideration the number of persons and their hot water consumption, and pattern in general.
What are the two majors factors affecting the performance of a properly installed SWH system?
Scaling in liquid or hydronic-based systems
Water containing high levels of minerals may cause a build-up or scaling of calcium deposits in hydronic solar heating systems. Scale build-up will substantially reduce the system’s performance in several ways. If your system uses water as the heat-transfer fluid, scaling can occur in the collector, distribution piping, and heat exchanger. In solar water heaters that use other types of heat-transfer fluids (such as glycol, an anti-freeze), scaling can also occur on the surface of the heat exchanger that transfers heat from the solar collector to the domestic water. In addition, it may also cause valve and pump failures on the potable water loop.
Corrosion in hydronic and air systems
Most well-designed solar water heater systems experience minimal corrosion. When they do, it is usually galvanic corrosion which is an electrolytic process caused by two different metals coming into contact. One metal will most likely have a stronger positive electrical charge and pulls electrons from the other metal, causing one of the metals to corrode. The heat-transfer fluid in some solar water heater systems may provide the bridge over which this exchange of electrons occurs.
Furthermore, oxygen entering into an open loop hydronic solar water heater will cause rust in any iron or steel component. Such systems should have copper, bronze, brass, stainless steel, plastic, rubber components in the plumbing loop, and plastic or glass lined storage tanks.
How much can a household save by investing in a solar water heater?
In Malta we are blessed with extensive periods and several months of sun practically all year round and as a result, we are very fortunate to enjoy very high levels of efficiency performance from solar water heaters. It is very hard to accurately convert all this to actual monetary savings on an individual basis however, it is estimated that on average a household could easily save in excess of €500 per annum.
