1. The hot water pipe of the solar water heater is more than ten meters long, and a lot of water is wasted every time it is used. Calculated on a typical Φ12 mm water pipe, 0.113 kg of water is stored per 1 meter of length. If the length of the solar hot water pipe is 15 meters on average, about 1.7 kg of water will be wasted each time it is used. If used 6 times a day on average, 10.2 kg of water is wasted every day; 360 kg of water is wasted every month; 4320 kg of water is wasted every year; 43,200 kg of water is wasted in ten years! To save some electricity at the cost of wasting water, I am afraid that neither the government nor the people would recognize this if they knew it. Among the more than 660 cities in China, more than half of the cities lack water to varying degrees, and 111 of them suffer from severe water shortages. The annual output value of the industry is more than 200 billion yuan due to water shortages.
2. The solar water heater needs a whole day of sunshine to heat the water. When the weather is good, it can only guarantee hot water at night, and there is very little hot water available during the day and night. The 24-hour hot water supply for the user cannot be guaranteed, and the comfort is poor.
3. The solar water heater's daylighting panels must be installed on the roof, which is bulky and heavy, and affects the beauty of the building (the more high-end residential areas, the more obvious), and it is easy to damage the roof waterproof layer.
4. The solar water heater's optoelectronics complement each other, but it can't actually be realized properly. 90% of solar water heaters in the market have a persistent problem that is difficult to overcome: the water temperature in winter cannot be reached, or only a small amount of hot water can be produced;
5. Another serious shortcoming is that more than 99% of the market is now very backward "non-pressure type" (including several strong brands in the solar water heater field, all of which are sold in this type of non-pressure type), commonly known as " Falling into the water". There is only one water pipe for water inlet and outlet, which is very inconvenient to use, and it is not comfortable at all.
