EcoRenovator - View Single Post - How much energy to heat 100 liters of water?

bernard · 10-13-15, 05:31 AM

There is something that has been confusing me for a while, and it is related with "types" of energies when it comes to heating water.

Here is an example:
volume of water to heat: 100 liters (26.4 gallons)
required water temp = 45°C (113°F)
mains water temp = 10°C (50°F)

So to heat 100 liters to upper temperature of 35°C, with an electric heater:

100 liters * (45-10) = 3500 kcal

1 kcal is equal to 1/860 kWh, so:

3500kcal / 860 ≈ 4 kWh (13.6 kBtu/h)

But this is an electric energy needed to heat upper 100 liters by 35°C.

What If I wanted to heat the same amount of water with gas? How would this example look like then?
And what would be the result then? Thermal energy in kWh?

How would I compare the thermal energy and electrical energy, even though they have the same units (kWh)?

Thank you for the reply.

10-13-15, 05:31 AM	#1
bernard Lurking Renovator Join Date: Sep 2015 Location: Hungary Posts: 22 Thanks: 9 Thanked 0 Times in 0 Posts	How much energy to heat 100 liters of water? There is something that has been confusing me for a while, and it is related with "types" of energies when it comes to heating water. Here is an example: volume of water to heat: 100 liters (26.4 gallons) required water temp = 45°C (113°F) mains water temp = 10°C (50°F) So to heat 100 liters to upper temperature of 35°C, with an electric heater: 100 liters * (45-10) = 3500 kcal 1 kcal is equal to 1/860 kWh, so: 3500kcal / 860 ≈ 4 kWh (13.6 kBtu/h) But this is an electric energy needed to heat upper 100 liters by 35°C. What If I wanted to heat the same amount of water with gas? How would this example look like then? And what would be the result then? Thermal energy in kWh? How would I compare the thermal energy and electrical energy, even though they have the same units (kWh)? Thank you for the reply.