As a green energy source, solar energy is being used more and more by human society. Because the heat output capability of solar water heaters is greatly affected by weather conditions such as sunshine, environment and temperature. In areas with unstable lighting conditions, the effect of the solar water heating system is restricted. However, in order to obtain hot water, household solar water heaters are almost always equipped with auxiliary heat sources. Among them, electric heating and gas are the most common. While making full use of solar energy, operating costs are reduced by auxiliary heating. In recent years, the use of auxiliary heat sources has become the only alternative to solar water heating systems.
1, Auxiliary heat source - electric heating
Electric heating is used as a backup heating method for solar water heaters, and is used when the hot water temperature does not meet the requirements for use. Generally used in integrated solar water heaters and split water tanks.
Because of the convenient installation and use of electric heating, electric heating is often chosen as an auxiliary heating method. However, the energy consumption ratio of electric heating is low, and as a secondary energy source, if electricity is completely used to heat water, the cost of electricity expenditure will be very expensive.
In addition, in some countries, electricity charges in some cities are calculated over time. In this case, if the daylight is not able to meet the conditions, the use of electric heating as the auxiliary heating to complete the heating during the billing period will be limited. In this case, electric heating is not recommended as a heating mode of the solar auxiliary heat source.
2, Auxiliary heat source - gas
Similarly, gas is used as auxiliary heating for heating domestic hot water, and its heat output capability is not affected by sunlight and meteorological conditions. It can be applied to split solar water heaters and solar heating systems.
The combination of solar water heaters and gas can maximize the use of solar energy while meeting the comfort of water. However, since the fuel used is non-renewable gas, on the one hand, the operation cost is high, and on the other hand, it is inevitable to discharge a certain amount of pollutants during operation, which causes certain harm to life and the environment. However, in a solar water heating system dominated by solar energy and gas, this has to be a necessary heating method.
3, The advantages of solar heating - efficient environmental protection and energy saving
As long as the traditional gas water heater uses hot water, it will start to burn the gas, and the cost of gas will continue to increase. But the biggest advantage is that you can quickly output hot water as long as you need to use it, regardless of the weather.
For traditional electric heating water heaters, the biggest limitation is the use of fixed water tank capacity, which has certain restrictions on the hot water and time used. At the same time, the resulting electricity bill will also be a small family expense.
If the solar water heating system is combined with gas or electric heating, mainly solar energy, gas or electric heating is used as a supplemental heating mode, there is a clear complementarity between solar energy and auxiliary heating. Not only that, but a one-time investment in solar heating systems can recover investment costs in 2-4 years. The solar heating system has a life span of 15-20 years, and the fixed income in the later period is obvious.
Today, coal, diesel, natural gas, etc. are all non-renewable energy sources, and will be less and less in the future development. However, their advantages have to be said that their high calorific value makes it easy to achieve high power and large water supply. The electric heating water heater works stably and is not affected by the weather environment. The solar water heating system, although it is more susceptible to weather (rainy weather, snowy days) in the process of use, but in the application process, it is more used with gas-heated boilers such as gas and electric heating. . This will not only reduce the cost of system operation, but also worry about the impact of weather factors and meet the needs of users under different conditions.