Charge your electric vehicle at home

The energy transition is also taking place on the road: More and more electric vehicles suitable for everyday use are ensuring the increasing electrification of transportation. An important goal of the mobility transition is to reduce CO₂ emissions in order to achieve climate protection targets. The charging current must then also be generated from renewable energies. PV system operators can charge their electric vehicle with electricity from their own PV system. Solar power from the roof thus is turned into green mileage on the road. Find out here how you can charge your electric vehicle safely and cost-effectively at home with the SMA charging solution.

Even in Germany, which is not exactly the sunniest country in the world, ten square meters of PV collector surface on your roof are theoretically enough to fuel around 10,000 kilometers of cost-effective, zero-emissions driving per year*. It doesn’t matter whether you are an experienced solar pioneer with your own PV system on the roof or a newcomer to solar power. You can integrate the SMA charging solution for e-mobility into an existing energy system at any time, even retrospectively.

*Calculation basis: Average consumption of electric vehicle: 18 kWh/100 km, collector area: 5 m²/kWp, annual yield: 950 kWh/kWp, as of December 2024.

Buying a wallbox: This is important

Since the beginning of 2024, the charging power of wallboxes in Germany must be controllable in accordance with Section 14a of the Energy Industry Act (EnWG). For this, they require at least one control input or an interface via which the power can be reduced to 4.2 kW if the power grid threatens to overload. The wallbox does not have to be switched off completely.

Intelligently linking PV power and e-mobility

There are smart and less smart solutions here. With the Sunny Home Manager 2.0 as an intelligent interface, the SMA charging solution is ideally matched to the components of the SMA Home Energy Solution. Sunny Home Manager 2.0 uses regional meteorological data to create a generation forecast, which it compares against your own consumption behavior. It then automatically controls the charging processes depending on the charge mode so that your solar power is fed to your car, not the utility grid. This allows you to optimize your self-consumption and save on the cost of grid-supplied power. Combined with a battery storage system, you can charge your car with solar power, even when the sun isn’t shining. And now you have your 24/7 accessible solar filling station on your doorstep. The charging system must always be registered with the grid operator. A wallbox with a charging capacity of more than 11 kW is also subject to approval.

Perfect partners: solar power and e-mobility

When charging, the SMA Wallbox automatically combines grid and solar power. This enables single-phase charging at 7.4 kilowatts, whereas conventional wallboxes usually only charge at 4.6 or 3.7 kW due to load imbalance. And thanks to the automatic switching between single-phase and three-phase operation, you can make optimum use of even the smallest solar outputs in the early morning and evening hours.

Your benefits:

• More cost-efficient mobility
• Increase self-consumption (PV)
• Reduce CO₂ emissions
• Amortization of PV system

And because you as a system operator ideally want to operate as many loads as possible with your PV power, SMA wallboxes dynamically adapt the charging power to the current conditions. This protects the house connection from overload and power failure.

Fast charging for electric vehicles: Flexible choice of charging mode

With an SMA charging solution, you decide for yourself how you want to charge your electric vehicle using the various charging modes: Particularly fast, PV-optimized or forecast-based? To do this, simply enter the charging destination in the SMA Energy app, i.e. the desired departure time and the amount of energy to be charged. The Sunny Home Manager 2.0 plans the charging process intelligently and at minimum cost – including guaranteed readiness for shutdown.

You can also conveniently switch between charging modes via the app. Using the SMA Energy App, you can easily control your charging processes and see at a glance how much of your valuable solar power is currently being converted to miles on the road. At the same time, the app allows you to keep an eye on the most important data of your energy system wherever you are.

Solar power refueling: reduce CO₂ footprint and relieve the grid

Charging your electric vehicle with solar power from your own roof is good for the environment, your wallet and the utility grid. If, on the other hand, the self-generated electricity ends up in an electric vehicle instead of the utility grid at peak times, this reduces the load and possible curtailment. This even allows more renewable energies and more electric vehicles to be integrated into the existing utility grid.

Here are two possible scenarios:

1. In one neighborhood, the charging processes pile up after work because the electric vehicles are being charged for the next day. This can place a heavy burden on the utility grid on site. Grid operators therefore offer attractive conditions for controllable charging stations that make it possible to limit the maximum charging power from the grid. The ability to control the charging station is also a prerequisite for many incentive programs. The SMA charging solution can be controlled in this way via a digital grid operator interface.
2. However, the local distribution grid is also put under strain if all PV systems feed in solar power at the same time. If the utility grid cannot absorb the entire amount of electricity, PV systems have to be curtailed.

Advantages of PV-optimized charging at a glance

• Use surplus PV energy and optimize self-consumption
• Cost-effective charging thanks to intelligent charging modes
• Independence from rising electricity prices and energy imports
• Faster charging of your electric vehicle
• Relieving the strain on the utility grid
• Zero-emissions mobility
• High level of safety thanks to power outage protection
• Connect up to three wallboxes to one Sunny Home Manager 2.0
• Automated and convenient service with SMA Smart Connected
• System solution from a single source

Your solar filling station for your home

You can find out more about the SMA EV Charger in these blog posts:

• https://www.sma-sunny.com/en/sma-ev-charger-your-questions-our-answers/
• https://www.sma-sunny.com/en/solar-optimized-charging/
• https://www.sma-sunny.com/en/more-sunshine-needed-in-the-tank/
• https://www.sma-sunny.com/en/how-forecast-based-charging-works/

Do you have any questions about Wallbox SMA eCharger? If so, please comment here by January 31, 2025. Our SMA e-mobility expert Lisa Spangenberg will answer the most common questions in a separate blog post soon.