calc.engineer / Solar & Power / Generator Offset

Generator Offset v1.0.0

Compares total cost of ownership between a fuel generator and a solar+battery system over a configurable time horizon. Calculates yearly and cumulative costs for generator-only, solar-only (amortized), and hybrid scenarios. Accounts for fuel cost, generator consumption rate, maintenance intervals, solar system amortization, and battery coverage. Outputs yearly costs, total savings, breakeven year, solar coverage percentage, and generator hours saved. Essential for off-grid site planning, remote telecom towers, construction sites, and rural electrification proposals.

← from solar_sizing.total_panel_watts← from solar_load_audit.total_daily_kwh
Fuel cost per gallon in USD, default $3.50
Generator fuel consumption in gallons per hour at load, default 1.0
Generator runtime hours per day, default 8
Generator maintenance cost per 1000 running hours in USD, default $200
Total solar+battery system cost in USD
Daily solar energy production in kWh
Battery storage capacity in kWh (0 means no battery, generator needed at night), default 0
Total daily energy requirement in kWh
Number of years to compare, default 10
Fill in the inputs and Compute to see the structured result.

From an agent (MCP) or the API

curl -X POST https://calc.engineer/api/generator_offset \
  -H "Content-Type: application/json" \
  -d '{"generator_fuel_cost_per_gallon": …, "generator_consumption_gph": …, "generator_hours_per_day": …}'

MCP: connect to https://calc.engineer/mcp and call generator_offset.

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