# How do you calculate energy losses in an energy grid?

Let's say you have an energy transmission line, that gets powered by an energy plant with a power of 6150MW. You know the line is for example 133 km long and you know the voltage of the power line is 380 kV. I am tempted to say you could calculate the energy loss of the line without taking any information about the power plant into account, calculating the power by P_loss=V²/R. However as mentionned before, we do not take the power of the plant into account so it could happen that you lose more heat than you produce energy. This is obviously not correct, so how should I solve this problem?

Question solved: Why high voltage transmission lines?

• If the losses due to resistance are to high in respect to the power of the power plant, it just means that a voltage that high cannot be maintained. Commented Mar 14, 2020 at 17:27

The first step is to define energy losses. When I hear that term regarding electrical grids, I typically assume they are referring to the $$P=I^2R$$ losses of the lines. This is because this particular loss is something that can be changed (by planning higher voltage lines).