EV Charging Standby

Charge the car on yesterday's sun.

An electric car usually charges in the evening, exactly when rooftop solar has stopped producing and grid prices are at their peak. The answer is to store daytime PV and release it at the charge session — a use case EMS-ESS explicitly supports as standby power for electric-vehicle charging. On negative-price days like Germany's minus €250/MWh on 11 May 2025, storing instead of exporting is the difference between profit and loss.

The Pain

Four costs of peak-time charging.

Demand charges, wasted solar, peak-rate grid draw and negative-price export define the EV charging problem.

Pain pointWhat the data says
Demand chargesDemand charges are the dominant cost problem at DC fast-charge sites; battery storage is the standard mitigation (AMpeco; Electric Era).
Wasted solarThe product brief lists standby power for electric-vehicle charging among supported scenarios (EMS-ESS residential ESS).
Utility upgradesBattery-backed EV charging buffers the grid and avoids costly utility upgrades (PandaExo).
Negative pricesOn Germany's minus €250/MWh days (11 May 2025), exporting PV is worthless; storing it and charging the car after dark is the better use.
Home with solar panels, energy storage and electric vehicle charging
Our Approach

Shift the charge, not the habit.

The driver plugs in at the same hour every day; the storage changes where the energy comes from. During the day the 8–12 kW hybrid inverter sends surplus PV into 5.12 kWh LiFePO4 modules (stacking to 40.96 kWh) instead of exporting at a loss. When the car connects, the system discharges that reserve through the charge point, so the session draws battery power rather than peak-rate grid power, and the site dodges the demand charge that a simultaneous charge-and-cool cycle would otherwise trigger.

  • Standby power for electric-vehicle charging, per the product brief
  • 5.12 kWh modules stack to 40.96 kWh for overnight charge sessions
  • 10 ms switchover keeps the charge session live through grid drops
  • Time-of-use scheduling charges on solar, discharges at peak
Requirement Mapping

How EV charging requirements map to EMS-ESS.

Each charging-site constraint maps to a certified, install-ready product parameter.

RequirementEMS-ESS response
System choice8–12 kW hybrid with PV + EV charging standby; reserve stored PV for evening charge sessions
Power range3–12 kW hybrid inverter; single-phase 3–5 kW, single/three-phase 8–12 kW
Capacity5.12 kWh LiFePO4 module, expandable 1–8 modules (5.12–40.96 kWh)
Switchover time10 ms (UPS, VDE); 20 ms (APL)
Input voltage90–280 V wide input, constant-voltage output (single-phase 176–270 V)
BatteryLiFePO4, 100% DOD, 10-year design life
Efficiency93% charge/discharge (3–5 kW); 98.2% (8–12 kW)
Grid standardVDE-AR-N 4105, G99, EN 50549-1, EN 62116
CertificationsCE, IEC 62109-1&-2, IEC 62477, UN38.3
Installation~5 min tool-free stacking, IP20 indoor, −15 °C to 55 °C
Warranty5-year product + 10-year performance warranty
MonitoringAPP + EMS cloud with remote fault diagnosis
How It Works

From inquiry to a solar-backed charger.

01

System selection

Share the charger power, session hours and PV size. We match an 8–12 kW hybrid and reserve plan — usually within one working day.

02

Grid files & samples

Test a sample against your local grid code. We deliver CE, IEC 62109 and UN38.3 files, English manuals and packaging specs for approval.

03

Install & maintain

Tool-free install in about 5 minutes, then APP + EMS cloud handles remote diagnosis. Warranty runs 5 years product, 10 years performance.

Proof Points

Verified facts behind the EV line.

  • Product brief lists standby power for electric-vehicle charging alongside residential, apartments, shops, offices and laboratories
  • Battery plus smart control raises solar self-consumption from ~30% to ~80% (Werner Solutions)
  • Germany's wholesale price hit minus €250/MWh on 11 May 2025 (Green Building Africa)
  • Distribution channels established in 20+ countries, with a German branch office

Charge on stored sun.

Send your charger power, session hours and PV size. We return a solar-backed EV charging plan and a quote within one working day.