Methodology & Assumptions

A carbon footprint is the total mass of greenhouse gases attributable to an activity or entity over a defined time period — usually one year. It is an accounting construct, not a physical measurement, and its value depends on the boundary you draw around the activity.

CarbonShift Pro draws a narrow, operational boundary on purpose: the energy you consume directly as electricity, heating fuel and transport. Food, goods, air travel, construction materials and the embodied emissions of equipment are out of scope.

Electricity emissions are calculated by multiplying annual electricity consumption by the grid emission intensity of the selected region. When you enter a monthly value, CarbonShift Pro scales it by 12. This ignores seasonal variation in both consumption and grid mix.

CO2e_electricity [kg CO2e/year] = E [kWh/year] × I_grid [kg CO2e/kWh]

E          = annual electricity consumption
             (or monthly consumption × 12)
I_grid     = regional grid emission intensity

E[kWh/year]

Annual electricity consumed at the meter. Read from a utility bill or estimated from monthly use.

I_grid[kg CO2e/kWh]

Average emissions per kilowatt-hour generated on the regional grid. A location-based average, not a marginal or market-based rate.

CO2e_electricity[kg CO2e/year]

Estimated annual greenhouse-gas emissions from electricity use.

Grid intensity is a regional average. It does not capture time-of-use variation, marginal generation, transmission losses beyond what the published factor includes, or a specific retail green-energy contract.

Annual solar generation is estimated from installed DC capacity, average equivalent full-sun hours per day, and a performance ratio that bundles inverter, thermal, soiling and wiring losses.

E_solar [kWh/year] = P [kWp] × H [h/day] × 365 [days/year] × PR

P  = installed DC capacity of the array
H  = average equivalent full-sun hours per day
PR = performance ratio (system losses)

E_solar[kWh/year]

Estimated annual solar energy production.

P[kWp]

Installed DC power rating of the photovoltaic array under standard test conditions (1,000 W/m², 25 °C).

H[h/day]

Average number of hours per day that the array receives irradiance equivalent to full sun. Strongly dependent on latitude, climate and season.

PR[ratio]

Performance ratio: the fraction of theoretical production actually delivered after inverter, thermal, soiling, shading, wiring and mismatch losses.

Avoided emissions assume generated solar energy displaces grid electricity at the regional average intensity. In practice, the avoided emissions depend on which generator is at the margin when the array produces.

The power available in wind increases with the cube of wind speed. Small-wind output is estimated from a simplified power relationship, then converted to annual energy using a capacity factor.

P_wind [W] = ½ × ρ [kg/m³] × A [m²] × v³ [m/s] × Cp × η

ρ  = air density
A  = swept area of the rotor
v  = wind speed
Cp = power coefficient (Betz-limit ideal ≈ 0.59, real turbines lower)
η  = combined drivetrain and electrical efficiency

ρ[kg/m³]

Air density. Lower at higher altitudes and higher temperatures.

A[m²]

Swept rotor area, roughly π × (blade diameter/2)². Doubling the diameter quadruples the swept area.

v[m/s]

Wind speed at hub height. Because power scales with v³, a 20% increase in wind speed roughly doubles available power.

Cp[ratio]

Power coefficient: the fraction of wind kinetic energy the rotor can extract. The theoretical Betz limit is ~59%; real turbines are typically 35–45%.

η[ratio]

Drivetrain, generator and electrical losses combined.

CarbonShift Pro converts this into annual energy using an illustrative capacity factor. Capacity factor is the single most sensitive input: a modest change in mean wind speed changes output substantially because available power scales with the cube of wind speed.

The table below lists the default parameters CarbonShift Pro uses when you do not override them. Every value is currently a placeholder and should be replaced with cited, published data before the results are used for any decision.

CarbonShift Pro is designed for education and early-stage exploration. It is not a substitute for professional services or official carbon accounting.

• Location-based grid intensity is used, not market-based or marginal accounting.
• The operational-energy boundary excludes embodied and consumption-chain emissions.
• Battery storage shifts energy; its emissions benefit depends on grid timing and dispatch.
• The ±20% uncertainty band is illustrative and not a propagated statistical uncertainty analysis.

CarbonShift Pro distinguishes three kinds of data so you can see where each number comes from and how much confidence to place in it.

Consumption entered from a utility bill is measured data that becomes user-provided input. Everything CarbonShift Pro returns is an estimate.

Factors are held in a single configuration module so they can be replaced without touching calculation or interface code. Replace the placeholder values with cited, published data, set verified: true, and update the source and year fields.