How Energy usage will change
Germany has an electricity need of about 600 TWh per year with a constant average energy load of about 55 GW. The BMWi says 2030 will have 655 TWh electricity demand, but that is peanuts if we take heat and mobility into account too. To go fully carbon neutral, we have to involve this too, so lets do a small calculation of a hypothetical model in the future.
Heat should be electrified 100% - according to this statistic we are using
- 2171.1 PJ heat in households (1645.9 PJ room+142.5 PJ process heat, 382.7 PJ hot water),
- 1737.7 PJ in the industry (138.2 PJ room, 1582.7 PJ process heat, 16.8 PJ hot water) and
- 698.7 PJ in sales (513.7 PJ room, 110.5PJ process, 74.5 hot water).
This results in 4607.5 PJ or 1280 TWh of heat. If we would use heat pumps with a coefficient of performance (COP) of not less than 3, which is reasonable for German temperature, we would still have to provide at most 426 TWh of additional electricity. According to the UBA, we need around 2500 PJ or 694 TWh of energy for transport. I could not find out if this is the net usage or the energy amount of burnt fuel, which would also be far less if electric cars were used due to their higher efficiency. More on this in a later post.
So in total, we need to provide 1710 TWh/a of electric energy if we get rid of fossil generation completely for all sectors (electricity, heat, and mobility). This corresponds to a constant demand of 195.07 GW, which is much higher than the 55 GW average we have now.
If storage would not cost anything, we would therefore build 1706 GWp of PV generation and storage with a size of 300446 GWh and call it a day as this model shows.
This is unrealistic as the rooftop potential in germany is between 161 GWp and 200 GWp. The last source also provides a number of 1300 TWh/a for Germany and 200-400 GWp of solar (including solar parks).
The land potential of wind is between 200-700 TWh while offshore is more than 60 GW
If we simulate our system in this case, we are fully using 400GW solar, 700GW wind and 132GW H2 turbines. Currently, the German electricity power system is at 62GW solar, 57GW wind and 0GW H2 turbines of renewables. That means that we are currently importing 694 TWh of gasoline and diesel and are using 1280 TWh for heating, with around 900 TWh of gas (in 2020 and 2021, 804 TWh in 2022 - according to entsog).
For me, it seems like a huge switch, but it also shows that the electricity market everyone looked at in the last years is only a small part of energy usage in total.
But there is a lot to improve and build for the future. If this would become a reality, the electricity grid could surely not withstand and increase of 300% total power consumption. This can surely not be solved by demand-side management only. But it won’t.
First of all, the produced heat of the H2 turbines can also be used for heating surrounding areas. It is unclear how the transport sector will change in the future and if we will reduce individual transport somehow. A 0 Emission model seems quite unrealistic, but even if we allow 146GW of gas turbines and set a limit of 100gCO2/kWh we need 100TWh of H2 storage which seems very far away from our current energy system.
Of course, this is just a model with all limitations and so on, but in the end, I would expect a real target to be not very far from this model.
- Costs here are for completely decarbonised electricity systems. Reaching lower levels of decarbonisation is much cheaper and doesn’t necessarily require any storage at all.
- Costs for the electricity grid inside each country and costs for ancillary services are not included.
But if one would calculate the cost for this, we would need to take the removed total cost of gas and oil into consideration too.
We live in interesting times.