Solar systems capture and collect the thermal energy from the sun transferring it to water, which is collected in a special water tank. They are becoming more and more popular and more widely used in many households. With their help you will save significant amounts of the electricity bills, you will have constantly hot water and help protect the environment. "Thinking green" is not just a fashion propagandized by the media. It is a necessity and does not end with the separation of the waste or turning off the power at home for one hour in only one day of the year.
The prognoses for the use of solar collectors suggest that by 2020 every second household will benefit from them. Having in mind the climate in Bulgaria, these predictions are entirely justified, since the temperature limits here fit into the working range of the vacuum solar collectors. Thus, throughout the whole year, you can be sure that you will have hot water without paying for extra costs and without polluting nature.
Why to use a solar water heating system?
Warming the water with solar energy has more than one advantage. Here are some key reasons why you should to use solar water heating systems at home.
On the one hand the use of solar energy can reduce your personal dependence on suppliers of electricity and fuels. On the other hand you are helping to reduce the extent of the dependence of the whole nation from foreign energy suppliers. Solar energy is just as reliable as the energy you get from the electricity or gas. In other words - while the sun shines, you will have a source of energy.
Many people that use similar systems, rarely use the other sources of energy. Such independence can be really nice.
Impact on the environment
It is a fact that most of the energy we use comes from the burning of fossil fuels. This leads to a wide range of environmental problems such as climate change, acid rain and health problems in the areas of power stations. The use of nuclear energy and the toxic waste from it, which do not degrade for thousands of years, is also a problem for many.
But why risk the environment when we can take advantage of the free solar rays that approach the Earth in order to satisfy our energy needs? Aside from the production of the panels to capture solar energy, in fact there is no negative influence on nature from its use.
Numerous studies serve that the average family of four spends around 6400 kWh of electricity for heating water for a year. If we assume that the generation of electricity from power plants has around 30% efficiency, then the electric water heater in the home is responsible for the disposal of 8 tonnes of carbon dioxide per year, as a by-product of the production of that energy. Natural gas also pollutes nature – approximately 2 tonnes per year.
When you choose a solar collector to satisfy a bigger or smaller part of the energy consumption in your home it will certainly reduce your bills for electricity or gas. Although the electric solar systems are more popular, the solar systems for warm water will save you more of your bills. You can get from 50 to 100% reduction of your costs for electricity or gas depending of course on the solar radiation of the region in which you live and the recent fuel prices.
How to use solar energy to warm the water?
Solar energy is easily integrated into the way of life of most people. Once the solar system is mounted, it rarely needs any support. The three main benefits of such a system are:
Hot water at home is perhaps the most famous advantage of the solar panels. Every home uses hot water every day for bathing, washing-up or washing by hand. The hot water is stored in a water tank to be used when necessary. A household may use even half of this amount of water.
Space heating is the less used application of the solar hot water systems. Their function is similar to home heating systems, except that the non-drinkable hot water circulate in built-in pipes and radiators or complement the work of the climate system.
Heating of a swimming pool is a very easy application of the technology for heating by solar energy. The required equipment is minimal and a way cheaper.
The Nippon solar systems are manufactured in accordance with modern technology so that they can take up to 96% of the solar energy. It is transformed into thermal energy which every household uses for their everyday needs.
The solar systems consist mainly of two components – water tank (boiler) and glass pipes. The glass, which they are made of, is a special one of borosilicate mixtures, which makes it much more selective and the sun rays pass through it without reflection, thus having losses of barely 4%. More and more people rely on solar collectors to have constantly hot water. They are high-quality, environmentally friendly and moreover they are saving you a lot of electricity bills. You can look at them as an extremely good investment that will be repaid in the shortest possible time.
There are two main types of collector systems - with vacuum pipes and with flat panels. Their working principle is one and the same, but their efficiency is different.
The solar systems with circular vacuum pipes possess the ability to "track" passively the sun from morning to night, i.e. they are able to capture the sun rays throughout the whole day. This way they can capture in maximum degree the energy coming close to Earth. Because of this, their effectiveness is growing over 2.5 times, as they no longer need a certain angle of incidence of the sun rays. The transformed thermal energy is in larger quantities and the electricity costs are lower.
Thanks to the pipe form, namely the design is what makes them favourites for use not only in households but also for heating hot water in hotels, restaurants, swimming pools and in various industrial processes.
Unlike the vacuum pipe solar collectors, the ones with flat panels are most effective at noon, when the sun rays fall perpendicularly on the collector. These types of systems are not able to track the sun and so lose the rays in the morning and in the late afternoon, which significantly lowers the amount of heat that is generated. For this reason, if you have selected collector systems of this type, it is better to use a tank with a larger volume in order to store the hot water for a longer period of time.
Nippon solar systems provide between 60 and 80% of the hot water in the household by the average. This indicator can vary from 90-100% in summer, to about 40-50% in winter. The main advantage of the modern solar collectors is that they are designed to absorb the infrared and ultraviolet rays of the sun that are constant throughout the year and not only during sunny days.
A popular misconception is that during the winter the collectors do not work, because there are plenty of cloudy and cold days. Practically, you do not need direct sunshine, since infrared rays reach the Earth even in cloudy, foggy and rainy weather. Therefore the vacuum solar collectors can operate all year round, even in cold winter days. But then what causes the difference in efficiency during different seasons?
The explanation lies in the temperature of the incoming water from the mains. In summer it is about 20-25 ° C, while in winter it can fall to 4-5 ° C. Another essential factor is the length of the day – in summer it reaches up to 15 hours, and during the winter it is reduced to 9 hours. It also matters the different angle at which sunlight penetrates the atmosphere during the various seasons.
Having in mind the price of the electric water heaters, which can be even 3 times lower than that of the vacuum solar collectors, many households are choosing them without thinking that the money saved from electricity can pay back the investment in solar systems in 2 or 3 years. If one thinks twice about the term of use of the vacuum solar collectors, anyone could conclude that after the initial investment it immediately begins to be repaid. For a very short period the initially invested sum is "paid back" 100% back, after that you are making a profit.
With a good maintenance the system can work for 30 years, which will save you a lot of money indeed. Although the electric boiler can provide hot water for a short time, it cannot pay back the sum of money invested in it. So despite the seemingly advantageous purchase, in the long term it turns out to be extremely bad investment.