kWh required to heat my swimming pool

Question

I am building a swimming pool 9 metres by 3 metres by 2 metres deep . I want to heat it with solar panels feeding electricity to a heat pump .

I need to know how many kWh of electricity I need to increase the pool temperature by 10 degrees Celsius . Then I can specify the system I require .

Answer 1

First, calculate the volume of water in the pool in cubic meters.

Next, calculate the mass of the water by multiplying the density of water in kg / m³ by the number of cubic meters.

Finally, using the specific heat of water (4182 J/kgC°), calculate the number of joules needed by multiplying the specific heat by the number of kg of water and the temperature change needed.

Convert joules to kilojoules by dividing by 1000. As kWh is electrical energy in kilojoules, divide the number of kilojoules calculated by 3600 (1 kWh = 3600 kJ).

Answer 2

Specific heat capacity of water is 4184 J / kg / K

volume = 9 x 3 x 2 = 54 m3 , 1m3 has mass 1000 kg, so 54000 kg mass

to raise temperature by 10 Celsius (also 10 K) you need 54000 x 4184 x 10 J = 2259360000 J

1 kWh = 3600 s x 1000 J/s = 3600000 J

So you need 2259360000/3600000 = 627.6 kwh