Schneider Finds Rooftop Solar, Batteries Cut System Costs Up to 40%

• Schneider Electric's research unit modelled 40,500 scenarios and found rooftop solar and batteries cut total system costs 10% at today's world-average prices.
• At 2030s costs the cut reaches 40%, but only if new demand from EVs, heat pumps and data centers grows alongside them.
• The US stays above the $160-per-MWh benchmark for now because installed residential solar costs three times the world average.

Rooftop solar and batteries can cut the total cost of an electricity system by 10% at today's world-average installed costs, and by 40% at costs projected for the 2030s, according to a report from the Schneider Electric Research Institute published Nov. 10. The catch is that electricity demand has to grow alongside them.

The study ran 40,500 scenarios. It adds the levelized cost of rooftop PV and home and building batteries to the fixed and variable costs of the central grid, measured against a benchmark of $160 per MWh before tax.

No real country was modelled. The grid is a conceptual mix of homes, offices and factories, in a building-heavy version close to Western economies and a more industrial one closer to China. Cost inputs cover current US prices, today's world average outside the US and a 2030s projection. The US is the outlier: residential solar there is assumed at $3 per watt installed, three times the world-average case.

The study in numbers

• $145 per MWh: lowest total system cost at today's world-average solar and battery prices.
• $94 per MWh at 2030s costs, $66 below the $160 benchmark (list.solar calculation).
• $191 per MWh in the US case, $31 above the benchmark (list.solar calculation).
• 79% drop in the assumed installed cost of a home battery, from $700 per kWh today to $150 in the 2030s (list.solar calculation).
• $140 per kWh, approximately: installed cost of four-hour utility-scale batteries in 2025, down close to 30%, according to IRENA.
• 35% above the benchmark: where a poor battery arrangement can push costs at today's world-average prices.
• 0.15% to 0.8% of GDP in potential additional income, from today to the 2030s.

Timing matters too. In the report's illustrative paths, costs rise to about $173 per MWh by 2035 if demand outruns rooftop systems. They peak near $168 around 2030 if solar and batteries come first. Moving both together holds the peak to about $163 and brings costs down to about $105 by 2050.

Laurent Bataille, Schneider Electric's executive vice president for Europe operations, said in a statement that "solar is the fuel, the battery is the power plant."

The model assumes surplus solar is stored or curtailed, never exported, and it leaves out physical network constraints. The authors say applied research on specific networks is still needed to confirm the findings.