There are ten main factors influencing business performance as homemade solar water heaters of capacity to supply hot water in an efficient and cost-effective manner.
If you take them into account when designing, planning and build your own system, you should be able to obtain a performance that compares very well to commercial systems.
And if you're buying a system commercially designed and built you know what to look for when choosing the most efficient.
Factors is based on the results obtained from the efficiency of the field measurements of these already installed solar water heater made in house and commercial systems of solar heating of water throughout the world.
1. The size of the storage tank - bigger not always is better, but in this case it is true. A large hot water storage tank maintains its contents hotter for a long period of time due to a property called thermal inertia. So that the bigger the tank is the more you will have in reserve to cover several cloudy days and the incoming cold water will have one minor effect in general when the hot water is drawn.
This is a great advantage that a homemade solar water heater has more than one trading system, since you can convert the tank without an increase in the astronomical cost.
Commercial deposits are more or less of the size by using the formula of 50 liters (13 gallons) per day of capacity to each person in one household other 50 liters (13 gallons) of household in general, but of a safe, cost-effective way to DIY system possible double estimate.
2. The surface of the solar collectors - this factor is quite obvious that the greater the surface of the water catchment more exposed to the heat of the Sun. Here again, the House made constructor solar water heater has an advantage over commercial units, since you can increase the size with only a small increase in cost of materials and effort.
The size of the storage tank is determined by the size of collectors with the golden rule in moderate to be 1.5 gallons (5.6 liters) per square foot (0.09 m) climates.
In warm climates, increase storage to 2 gallons (7.5 liters) per foot (0.09 m) square. If you do not get the proper proportion, there is a chance that the system from overheating during the summer or not heating enough during the winter.
3. Collector materials Used - traditional (commercial) solar collectors have tubes of copper connected to absorb copper fins heat because this provides the best thermal performance, but at a higher price. Homemade solar water heater can be at a cost much lower than using copper tubes attached to the aluminium fins and have almost the same performance. Pex tube / aluminium fins cost about 1/6th the price of commercials with loss of approximately 15% in performance (source: Builditsolar).
4 Angle of tilt and orientation of the collectors - in general, homemade solar collectors of the boiler in the southern hemisphere should face northward and in the northern hemisphere, to the South. The optimum tilt angle mounting the collectors should be equal to the latitude of your location, but the difference in the only performance will be noticed if the angle is more than 10% out.
5. Heat exchanger of coil material and dimensions - copper heat exchangers are the best but arrives that Banisher before, high-cost. To make things more affordable a pex / copper pex hybrid or pure heat exchanger is acceptable, but it will be less efficient than the equivalent copper. The longest of the coil, more water can be heated at the same time, by one inch (2.54 cm) 1 diameter of 300 feet (91.44 meters) of the pipe coil can contain 45,42 12 gallons of water (source: Builditsolar) which will be very efficient because the warm water attracts many have less than that volume.
6 Tanks and pipes - insulation is important to insulate properly because the heat lost less than expected longer the water stays hot and less of the water heater solar home system has to work to warm up again. Also help to prolong the time of hot water available in Misty conditions.
7 Hot water demand - more hot water you are using, the worst of your system be carried out due to the fact you have to heat a larger volume of incoming cold water to the desired temperature. So the more we consume, the higher will be its cost of operation is going to be because the strengthening of backup (electric or gas) comes into play more often.
8. The obstructions of the site – its commercial and homemade solar hot water collectors must be located so that they both get exposure to the Sun as possible and that means making sure that obstructions such as trees are taken into account before deciding where to place them.
9. Geographical location - is closer to the ecuador, provide more energy from the Sun to heat the water, due to the fact that the surface of the Earth towards the Sun directly there. Action that moves towards the North or South of the Earth's curvature means that the same amount of the Sun's rays covers a larger surface area and therefore reduces the energy supplied.
The luxury for this term is called solar insolation which is a measure of the amount of solar energy received in a given area during a given time.
10 Weather - there's not much that can be done to alter the climate, except for decision in another place but which will have an important impact on the performance of a heater of home and commercial solar water due to temperature variations and the clouds. NASA estimates that on average globally only 57% of the sunlight that hits the upper atmosphere reaches the surface of the Earth due to cloud cover and contamination.