How Much Solar Surplus Can Charge Your EV?
Estimate the solar energy left after normal site consumption and determine how much of that surplus can reach an electric vehicle after EV charging losses.
What solar surplus means for EV charging
Solar surplus is generation that remains after the site's other electricity demand has been served. That surplus can potentially charge an EV instead of being exported or curtailed.
Why surplus depends on timing
Daily energy totals are useful for screening but do not prove that the solar and EV charging occur at the same time. A detailed plan should use interval solar production and site-load data.
Charging losses matter
The EV must receive less energy than the electricity supplied to the charger when charging losses occur. The calculator therefore converts available solar surplus into delivered EV energy after the stated loss assumption.
Why excess solar is not automatically free
Solar surplus can have an alternative value, such as export compensation. The avoided-cost figure here represents avoided grid purchases and does not assign a value to export opportunity cost.
FAQs
Can the EV use all daily solar surplus?
Only when charging capacity, vehicle availability and timing permit it.
Does this model battery storage between solar and EV charging?
No. This is direct surplus-energy screening.
Can the result be zero?
Yes. If site consumption uses all available solar, no direct surplus remains.
Does the grid-rate input represent export value?
No. It represents avoided grid electricity cost.