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Green Energy Tariffs for Business: REGO, PPA and Genuine Additionality

Not all renewable business tariffs are equal. Here is how to tell a certificate-backed tariff from one that genuinely adds capacity.

22 June 2026 7 min read

How REGO-backed tariffs work

Most 'green' business tariffs are backed by Renewable Energy Guarantees of Origin — certificates that match your consumption to renewable generation somewhere on the grid. They are legitimate for reporting purposes but do not, on their own, cause new renewable capacity to be built.

PPAs and additionality

A corporate power purchase agreement contracts directly with a generator, often for ten years or more. It provides genuine additionality and long-term price stability, but requires scale and a strong balance sheet.

Choosing what matches your claims

If your marketing says 'powered by renewables', make sure the evidence supports it. Ask for the fuel mix disclosure and the certificate retirement statement. Green claims you cannot evidence are a reputational risk that outweighs the marketing benefit.

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