Negative prices? Bring it on!

Here I am at 1pm on a nice, sunny day. Plenty of solar energy being generated and my Tesla Powerwall will soon be full…

Then what do I see? This…

Energy being imported from the grid

Brighte is running my battery system and it’s buying power from the grid. This seems a bit strange because there’s plenty of sun and my battery will fill up without help from the grid.

So, let’s take a look at the wholesale cost of energy at the moment:

It’s negative, which means that there’s too much power in the grid due to lots of rooftop solar generation and low demand. This has been pretty common lately. I’ve been told that Spring is a great time for solar generation because there’s plenty of sun but not a lot of demand because it’s not too hot.

Since I’m on an energy plan with Brighte (disclaimer: I work for them), they are trying to optimise my solar and battery system to minimise their costs. Basically, they try to save money or earn money out of my battery and in exchange give me a lower energy bill.

The graph suggests that the price of electricity will climb this afternoon, so they must be buying power now at a negative cost, which earns them money! Later, when my battery is full, my system will automatically sell power to the grid, but it will hopefully be ‘less negative’ than it is now, so they have earned money on the activity (or at least ‘lost less’). While there is a Network Tariff for importing the power (about 5.6c/kWh looking at the Energy Australia tariff list), they must be hoping to come out in-front.

I think it’s time to run my pool pump at maximum, to take advantage of all this excess energy!