@Mocarquer I would argue that there are reasonable differences between the summary reports of the two models that are not very little.
- Case 1 has less total site energy. This is because of the solar plate collectors providing hot water to the water heater, which reduces the amount of energy used at the site (aka the building itself).
- Because the water heater uses natural gas, the difference in total site energy results in an almost equal difference in total source energy. This is because the default site-to-source conversion factor for natural gas is 1.084 (see below). These conversion factors can be set by the user using FuelFactors objects.
- Case 1 has negative Net Site Energy, while Case 2 has the same value for both Net Site Energy and Total Site Energy. This is because of the PV panels in Case 1 reducing the amount of electricity the building requires from the grid or utility. The negative value indicates that the PV panels are generating more electricity than the building consumes.
