First, look at the duration of sunshine in your urban area (region). For example: Kunming, Yunnan, has a long sunshine period, a short frost period, an average annual temperature of 15℃, and an average annual sunshine of about 2,200 hours. But this is not the case in Guiyang, where the sky has not been sunny for three days! If you often don't see the sun for a month or two, solar energy is not suitable!
Second, look at the brand and price; in addition to local outlets, the brand also has professional services online stores; it is not recommended that the price exceeds 3,000 yuan for Huangming, Siji Muge, etc., more than 2,000 for others, and even 1,000 several! “Exchanging old items for new ones” is just a promotional method used by merchants!
If the sunshine duration in your area is less than 240 days, it is not recommended to useuse solar energy, because when there is no sun you have to rely on electric heating. energy consumption is high. It's not as good as an electric water heater; For ordinary households, natural gas and electric water heaters without natural gas are preferable. If possible, air-to-energy water heaters can be considered! The 200 liters of air used in my house in Changsha, Hunan, can support my four children and two children (the children take a bath every day), cook rice, stew soup (the children prepare rice separately), warm the fire in winter, and turn on the air conditioner less in summer. There is still a little left from the annual electricity bill of €1,500. The emphasis is on safety and comfort (large water flow), and energy savings take second place!