Balcony wall-mounted solar power can generally hold 80 liters or 100 liters of water. It is rare to hold 120 liters and 150 liters of water. The solar energy of glass vacuum tubes is related to the inner diameter and number of vacuum tubes. Generally, the diameter is 58, and each tube with a length of 1 or 6 is less than 100 liters of water, 1.8 meters less than 2.5 liters of water.
Solar water heater is a heating device that converts solar energy into thermal energy, heating water from low temperature to high temperature to meet usage hot water by people in life and production. Solar water heaters are divided into vacuum tube solar water heaters and flat panel solar water heaters based on their structural shapes.
There is a solar water heater with a total capacity of 80L. Install it on a sunny horizontal surface and fill it with water. (1) Every day(sunny day) in this area
(1) Solar energy received in one day:
E=2.8×106J/(m2?h)×1.5m2 ×8h =3.36 ×107J,
Q suction=ηE=60%×3.36×107J=2.016×107J,
∵Q suction=cm△t, m=ρV =1 ×103kg/m3 ×80×10-3m3=80kg，
∴△t=
| Aspiration Q | ||||||
| cm | < /tr>< /table>=
| 2.016 × 107J |
| 4.2 × 103J/( kg?℃) ×80kg |
(2) According to the question, Q absorbs = η′Q releases,
then Q releases =
| Aspiration Q |
| η′ |
set by Q =mq Get: m′=
| Q put |
| q |
| 2.88×107J |
| 8×107J/kg |
Answer: (1) Solar energy received in oneday is about 3.36×107J if 60% of this solar energy is absorbed by the water contained in the water. water heater, the water temperature can be increased by 60 ℃;
(2) Switching to solar water heaters can save an average of 0.36 kg of liquefied petroleum gas per day;
(3) Using solar energy can save fossil energy and reduce environmental pollution
| Solution: (1) The mass of water in the water heater. : m of water＝ρV＝1×10 3 kg/m 3 ×80×10 -3 m 3 ＝80kg Heat absorbed by the water in the water heater: Q absorption=Q total η=Q total 60%=3.36×10 7 J×60%=2.016×10 7 J, It can be seen from Q absorption = c water m water △t, △t= = =60℃; (2) How many cubic meters of liquefied gas are completely burned: From Q= Vq, we can see that V= = 3.36×10 7 J/4.9×10 7 J/m 3 =0.69 m 3 . (3) ① Save non-renewable energy; protect the environment and preventez pollution. ②Easily constrained by weather conditions and environment. |