Calculators
Energy & Solar
System sizing, output and what it really saves
6 calculators
BTU Calculator – HVAC Sizing for Heating & CoolingSizes to climate and envelope, and shows why an oversized system is the worse mistake.STC Calculator – Solar Rebate Certificates 2026Zone rating and deeming years, floored as the regulator actually creates certificates.Solar Battery CalculatorSized by solar surplus as well as evening load, with the tiered federal rebate.Cable Size CalculatorSolves both constraints, because on long runs voltage drop governs, not current.Electricity Cost CalculatorSeparates the fixed supply charge from usage, which is why your effective rate is higher.Solar Panel CalculatorSizes from real derate factors, and shows why self-consumption beats system size.
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