SimpleHeatExchanger efficiency

[gitlaxy]

Hi,

I'm learning how to use TESpy. I started with the District Heating Network example.

I'm running the example just before the Changing Operating Conditions.

My only change to the example was the heat load: I increased the load from -10,000 Watts to -4,100,000 Watts.

So, the only change is from cons.set_attr(Q=-10000, pr=0.98) to cons.set_attr(Q=-4100000, pr=0.98)

However after the change above the heat source is lower than the heat demand. According to the Results:

Consumer Q = -4.10e+06
heat source Q = 4.08e+06

Yielding an efficiency higher than 1!.

With the original code, i.e., Consumer Q = -10,000 Watts the efficiency is ca. 0.96.

Any ideas why am I getting such results with the consumer load of -4,100,000 Watts?

[fwitte]

Hi!

That is because the power drawn by the pump is not factored in, which is about 16 kW in your case.

Best

[gitlaxy]

Thanks.

Just as a reference, those 16 kW can be obtained with this line of code:
print(pu.P.val); where P is in Watts.

[fwitte]

Great, thank you for the feedback. So maybe this piece of information should be added to the tutorial.

[fwitte]

Adpoted it already, should be available on the documentation page very soon