What Scope 2 is — and why solar is the fastest lever
The GHG Protocol splits a company’s emissions into three scopes. Scope 1 is what you burn directly (a generator, a boiler). Scope 3 is your value chain. Scope 2 is the emissions embodied in the electricity you purchase from the grid — and for most commercial and industrial sites it is the single largest, most controllable category.
Because Scope 2 is “bought” electricity, the fastest way to cut it is to buy less of it. On-site solar does exactly that: every kilowatt-hour you generate and consume yourself is a kilowatt-hour you did not draw from the grid, so it carries no Scope 2 emission. Reporting guides consistently call on-site solar the fastest, most measurable first action a business can take on Scope 2.
Location-based vs market-based — the two ways you must report
Under the GHG Protocol, companies report Scope 2 two ways at once (“dual reporting”). This distinction is where solar evidence starts to matter.
| Method | What it measures | Evidence it needs |
|---|---|---|
| Location-based | Grid-average emissions for your region | Your metered grid consumption × the regional grid factor |
| Market-based | Your actual purchases — contracts, tariffs, RECs, and on-site generation | Per-MWh proof of the clean energy you generated or procured |
The catch: your Scope 2 number is only as good as its source data
It is easy to estimate a solar reduction. It is much harder to prove it. The market-based method — and the renewable-energy certificates (RECs / I-RECs) that often go with it — requires auditable evidence of how many units your system actually produced, per site and over time.
Assurance is tightening fast. Under regimes such as the EU’s CSRD and California’s SB 253, Scope 2 disclosures are moving from limited to reasonable assurance, and auditors increasingly demand a data trail showing where every number came from. A spreadsheet total from an inverter app is not that trail.
- A market-based Scope 2 claim needs per-MWh generation evidence, not an annual estimate.
- RECs / I-RECs each represent 1 MWh and require auditable data on the origin and generation of that energy.
- Assurance-grade reporting needs traceability — a record of production that a third party can check.
Where BijliBachao fits — the measurement layer, not the calculator
This is the layer BijliBachao’s Solar Performance Cloud (SPC) provides. SPC continuously inspects a solar plant string by string and keeps an independent, auditable record of what each part actually generated, across every major inverter brand in one view. That record is the assurance-grade source data a market-based Scope 2 claim or a REC issuance is built on.
Two honest boundaries. First, SPC measures generation; it does not compute your carbon number or issue certificates — it is the source layer that feeds them. Second, its records are “aligned to” the relevant monitoring standards (for example IEC 61724-1), not a certification of your report. What it removes is the weakest link in a solar Scope 2 claim: unverifiable generation data.
