Of course you all are wondering when this investment is going to make sense. So therefore I did a quick calculation for you all. Also some photo's
The current electricity rates in the Netherlands are about €0.18/KWh and gas is about €0.58/m3 on average.
My on-demand water heater had an efficiency of 67% and the caloric value of gas is 35MJ/m3. Which means that the old heater cost €0.025/MJ.
1 KWh costs €0.18 and contains 3.6MJ. So computing all of that means that a COP of 2.02 is the break even point.
The unit should be capable of a COP of 3.1 with an inlet temperature of 15 C. This will pretty much be always possible, since the unit is using the exhaust air to heat up the water.
So with that in mind the cost savings should be some 50%, of course this is without standby losses. I have no idea how much these losses actually are. So if someone could help me out with that it would be much appreciated.
