Scope 2 Claims for a Campus Solar VPPA
A university in a deregulated U.S. market consumes 28,000 MWh per year, with a peak demand of 4.6 MW. It is evaluating three claims for its sustainability report: (1) an off-site virtual power purchase agreement (VPPA) for an 8 MW solar project in the same grid region, expected to generate 16,000 MWh in a typical year but not yet operational; (2) 5,000 MWh of unbundled renewable energy certificates (RECs) purchased for the current year; and (3) a proposed on-site 1 MW rooftop PV system. The current-year grid location-based emission factor is 0.42 tCO2/MWh, and the market-based residual mix factor is 0.58 tCO2/MWh. The university's current-year electricity is 28,000 MWh. The VPPA contract is signed but the project will not deliver until next year. The RECs are Green-e certified and retired on the university's behalf. The university wants to announce that it is 100% renewable and carbon neutral for electricity this year.
1. Calculate current-year location-based and market-based Scope 2 emissions, and evaluate whether the 100% renewable claim is supportable this year.
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Use the dual-reporting approach required by the GHG Protocol Scope 2 Guidance.
- Location-based: 28,000 MWh x 0.42 tCO2/MWh = 11,760 tCO2.
- Market-based: only the current-year retired RECs can be applied. The VPPA is not yet operational, so its 16,000 MWh cannot be used this year. Uncovered load = 28,000 - 5,000 = 23,000 MWh. Market-based emissions = 23,000 x 0.58 = 13,340 tCO2.
The market-based result can be higher than the location-based result because the residual mix factor is higher than the grid average. That is not an error; it reflects the instruments actually retired.
The 100% renewable claim is not supportable. Only 5,000 MWh / 28,000 MWh = 17.9% of electricity is covered by current-year RECs. The VPPA is future delivery, not current-year supply. The carbon-neutral claim is also not supportable: 13,340 tCO2 remain on a market-based basis, and 11,760 tCO2 remain on a location-based basis. Even next year, the VPPA plus RECs would cover 21,000 MWh, or 75% of load, not 100%.
2. Assess the VPPA's additionality and accounting treatment. What conditions must be met before its output and RECs can be used to reduce Scope 2?
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Additionality means the renewable project would not have been built without the university's contract. A signed VPPA for a project that is not yet operational can be additional if the contract is material to financing and the project is not already mandated or built for another buyer. The university should document the project's counterfactual and avoid claiming additionality for a project that was already under construction for other reasons.
For market-based Scope 2 accounting, the VPPA output must be represented by contractual instruments that:
- Convey the renewable energy attributes to the university.
- Are tracked and retired on the university's behalf.
- Come from the same market boundary as the load.
- Have a vintage that matches the reporting year.
- Are not double-counted or sold to another party.
The VPPA does not physically deliver electricity to campus, so it cannot reduce location-based emissions. It can reduce market-based emissions only when the project is operating and the associated RECs are retired. The university should report both location-based and market-based totals and explain the contractual instruments. It should not use future VPPA output as if it were current-year supply.
3. Recommend a procurement and accounting strategy for the next three years, considering cost, risk, and the on-site PV option.
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Start with load reduction and on-site PV, because they reduce exposure and do not depend on market instruments. A 1 MW rooftop array might generate roughly 1,300 to 1,500 MWh/yr, or about 5% of load. That is useful but far short of 28,000 MWh, so it cannot support a 100% claim by itself.
Use the VPPA once it is operational, but only count delivered and retired RECs for the matching year. Do not count construction-stage output. Consider contract length, settlement price risk, project completion risk, and whether the project is genuinely additional. If the university wants stronger hourly matching, pair the VPPA with storage or shape the contract, but recognize that hourly matching is more expensive than annual matching.
Use unbundled RECs only as a bridge for the current year, and disclose that they are lower-additionality than a new project. They are cheap and can cover a known gap, but they do not build new renewables.
Accounting strategy:
- Report location-based and market-based Scope 2 every year.
- Set interim renewable and emissions targets, not a binary 100% claim.
- Do not claim carbon neutral until residual emissions are addressed with high-quality offsets and the claim boundary is clear.
- Reassess the 1 MW PV, VPPA, and REC mix annually against cost and delivery risk.