How Solar Energy EV Charging Works?

Fill up your EV with your own solar energy ev charging:what requirements must be met for this? Which technologies are useful? And how to avoid loading problems? A guide containing the most important information and tips:

• Trend: Self-use rather than grid connection
• Cost advantages: with electric vehicles, the profitability of PV systems can be significantly increased
• Important things to keep in mind: the right loading strategy for each case
• PV system sizing, energy control and EV technology must be coordinated
• Residual power: theory and practice

Because the combination of an electric vehicle and your own PV system makes economic and ecological sense. The reason: The average cost of producing so-called electricity (the cost of converting energy from another form of energy into electricity) from a home solar system (without storage) is between 5 and 11 cents per kWh. However, electricity fed into the public grid currently pays only 7 to 8 cents.

In this regard, it is recommended that you use every kilowatt hour you generate yourself. The payoff is much better. For example, if instead of charging your electric car at 30 cents/kWh, you charge cheap photovoltaic power into your electric car at 10 cents/kWh, the cost of travel drops from 6 euros to 2 euros per 100 kilometers.

Of course, the PV system must be large enough to provide enough power for the house and the car. The rule of thumb is that a PV system with a peak output of 10,000 kilowatts (10 kWp) produces a realistic 8,000 kWh of electricity per year, even more in sunny areas. An electric car driving 10,000 km per year is estimated to use around 2,000 kWh of electricity. Therefore, the household surplus (4,000 kWh) is more than sufficient.

Smaller systems, such as those found on the roofs of narrow terraced houses, usually only partially meet the additional demand for car power.10 The calculation for kWp systems is only valid if the potential of the system is actually increased – which is not easy in practice. This is because it means that the solar charging of the car will continue as soon as there is excess power.

The problem: Electric cars are often driven on the road, especially in the middle of the day when the sun is at its highest. The best example of this is a commuter’s car. Also, if the car is parked in a carport when the sun is at its peak, it can happen that the battery is quite full. The excess power may then have to be fed back into the grid.

In addition, there are seasonal ups and downs in electricity production: in the summer, there is usually more than enough PV surplus. In winter, on the other hand, it is difficult to generate enough PV power for the house, let alone for the car.

In this respect, the following applies: Exploiting the energy potential is a noble goal, but difficult to achieve in practice. Solar energy is not based on the availability of cars. Conversely, this is a good thing: If electricity users – at least as much as possible – depend on the availability of electricity

In addition to natural obstacles, there are also technical and financial barriers: not every electric car is equipped in such a way that it can be charged by a photovoltaic system. Backup batteries in the house can at least partially compensate for fluctuating power generation, significantly pushing up investment costs. As you can see, the combination of an electric car and your own photovoltaic system is not an absolute success. But working with her is worth it.