Creation from solar energy

Combining solar water heaters and electric water heaters to create a simple, inexpensive device that provides hot water, helping people have hot water all year round without spending money. Electricity cost is a topic that two students at Trung Hoa Middle School and High School successfully persuaded the jury to win the first prize at the science and technology innovation contest just held by the Department of Education and Training. Training Quang Binh province has just organized.
Talking about the reason for choosing the topic “Solution to use solar water heater in unstable weather (rainy, sunny) areas”, Dinh Thi Kim Oanh, a student of grade 12B, Middle School and High School Hoa shared: Currently, people use hot water mainly through water heaters, cooking hot water by electricity or by firewood, so it costs money.

Meanwhile, there is an inexhaustible source of energy, which is solar energy, which is being used in many constructions serving human life. The use of hot water by solar energy has also been implemented, but in unstable weather areas such as central provinces, especially Quang Binh, it is difficult to apply solar energy to generate electricity. Year-round hot water for daily living. Two children Dinh Thi Kim Oanh and Kaohsiung Cuong with the structural diagram of a solar water heater product. To solve this problem, Dinh Thi Kim Oanh, a student of class 12B and Kaohsiung Cuong, a student of class 12A, Trung Hoa Middle School and High School together with teacher Dinh Ngoc Trai researched and manufactured ordinary products. hot water by combining a solar water heater with an electric water heater. The principle of operation of this device is: the output of the solar water heater will be put through the inlet of the electric water heater, the output of the electric water heater will be brought down to the faucet. to use. The electricity supplied to the electric water heater is controlled by a controller with a temperature sensor. The temperature sensor head is located in the heart of the solar water heater. If the temperature in the solar water heater reaches 40 degrees Celsius or more (this temperature value can be adjusted), the controller will control the relay to disconnect the power to the electric water heater. At this time, hot water from the solar water heater flows through the electric water heater and flows down the faucet for use. If the temperature in the solar water heater is lower than 40 degrees Celsius, the controller will control the relay to power on the electric water heater. At this time, the water from the solar water heater flows through the electric water heater, here, the water will be heated to a certain temperature (depending on the user’s adjustment) and flows down the faucet for use. . The amount of electricity used to heat the water will be less because the water in the solar water heater itself is already heated more than normal water (during sunny days or hot temperatures). According to Kaohsiung, the outstanding advantage of this product is that it has come up with a solution to use solar water heaters in unstable rainy and sunny areas, namely the combination of using between the solar water heater and the electric water heater in a reasonable way. The power supply to the electric water heater is controlled to close and disconnect automatically on the basis of recognizing the water temperature in the solar water heater. This is the outstanding feature of the product, which helps to maximize the amount of electricity used to heat water. Without this automatic controller, according to habit, users will turn on the attomat to have hot water but forget that that day, it was sunny and there was hot water in the solar water heater. This habit will consume an unnecessary amount of power. But if there is this controller, the power supply for the electric water heater is fully automatic and scientific, depending on the water temperature in the solar water heater. Only when the temperature of the water in the solar water heater is too low (below 40 degrees Celsius), then the controller will output a signal to the relay to close the electric lock to supply power to the electric water heater. to boil water. Currently, the demand for hot water in daily life is very large. Therefore, in areas with erratic rainy and sunny weather that must use an electric water heater, the monthly electricity consumption is not small. But if installed in combination with another solar water heater, can significantly save monthly electricity consumption. According to the current quote, a 130l solar water heater (for a family of about 5 people) costs from 3.7 million VND, with a warranty of up to 5 years, a lifespan from 10 years to 15 years. The low initial cost but can be used for a long time and help consumers use hot water all year round without having to pay a lot of electricity bills is the obvious economic benefit of the project. Moreover, solar energy is a clean energy source that does not pollute the environment, therefore, if the product of the project is widely used, it will contribute to environmental protection. “We are very confident with this topic, because after completing the project, we were facilitated by our parents to install it right in our family to use. We are ready to support and guide the design and installation stages for families who need to use solar water heaters. Hopefully, our project will receive the investment of businesses to make products that are both technical and cheap to serve the needs of the people,” shared Dinh Thi Kim Oanh.