Renewable Energy Procurement: A Practical Guide for UK Businesses

How to source power you can actually prove is renewable, from green tariffs and REGOs through to corporate PPAs and on-site solar.

Renewable Energy Procurement – Buying business energy used to be straightforward. You picked a supplier, fixed a rate, and moved on. For a lot of UK firms that is no longer enough. Customers, investors and tender panels increasingly want proof of where the power comes from, and “we are on a green tariff” rarely survives a second question.

Renewable energy procurement is how you answer with evidence instead of a vague claim. Get it right and it lowers your reported emissions, underpins a credible net zero strategy, and can shelter you from some of the volatility tied to gas-fired generation. Get it wrong and you are paying a premium for a certificate that proves very little. The gap between the two comes down to detail.

What Renewable Energy Procurement Actually Means

At its simplest, renewable energy procurement is the process of sourcing your electricity from wind, solar, hydro or other renewable generation, and being able to demonstrate it. The demonstrating part matters as much as the buying.

In Great Britain the proof sits in a certificate scheme. Every megawatt hour of accredited renewable output earns one Renewable Energy Guarantee of Origin, or REGO, issued by Ofgem. Suppliers use these to back the green claims on the tariffs they sell.

So when you procure renewable power, what you are really buying is electricity plus the certificates that let you report it as zero-carbon under market-based accounting. Understanding that distinction is the first step to doing it well.

The Main Routes to Buying Renewable Power

There is no single way to do this. The right route depends on your size, your sites and how seriously your stakeholders scrutinise the claim. Broadly, four options dominate.

A green tariff is the easiest entry point. Your existing supplier sells you a renewable-backed contract and retires the certificates for you. Little effort, modest premium, weakest story.

A matched supply contract goes further, pairing your consumption with certificates from named generators. A sleeved power purchase agreement ties you directly to a specific wind or solar farm through your supplier. And on-site generation, typically rooftop solar, lets you produce power yourself.

Most larger buyers end up combining two or three of these rather than relying on one.

REGOs: What “100% Renewable” Really Proves

Here is where a lot of green tariffs come unstuck. A supplier can buy cheap, unbundled REGOs separately from the electricity itself, then use them to label an otherwise ordinary supply as “100% renewable”. Technically accurate. Not especially meaningful.

Bought this way, the certificates cost only pennies per megawatt hour, which is why the premium on many green tariffs is so small. They do nothing to bring new renewable capacity onto the grid, and a sharp procurement team on the other side of a tender will know it.

If your renewable energy procurement needs to stand up to scrutiny, look for supply that bundles the power and the certificates from the same generation, or move toward a PPA.

Corporate PPAs: The Serious Option

A corporate power purchase agreement is a long-term contract to buy electricity from a particular renewable project, often for ten years or more. Because your commitment helps the developer secure finance, a PPA can genuinely add new clean capacity to the system. That additionality is the claim that carries weight with bodies such as the Science Based Targets initiative.

PPAs are not for everyone. They suit organisations with sizeable, fairly predictable demand and the appetite to take a longer view on price. In return you get a credible story and, in many cases, a degree of insulation from wholesale market spikes.

The trade-off is complexity. Contract structure, volume shape and credit terms all need careful handling, which is why most businesses bring in help before signing one.

Generating Your Own Power

Nothing beats consuming electricity you generated on your own roof. On-site solar panels cut the volume you need to buy at all, sidestep network and policy charges on that portion, and produce the most defensible renewable claim there is.

The drawbacks are the upfront capital and the fact that few sites can cover all their demand this way. So on-site generation tends to work best as one layer of a wider plan rather than the whole answer. You self-supply what you can, then procure the remainder through tariffs or a PPA.

That blend is increasingly normal among the manufacturers and multi-site operators we work with.

Building a Renewable Energy Procurement Strategy

The mistake we see most often is treating this as a tick-box exercise. A business switches to a cheap green tariff, declares itself renewable, then gets caught out when a client asks for the underlying detail.

A proper renewable energy procurement strategy starts from what you are trying to prove and works back to the right mix of certificates, contracts and on-site generation. It should sit inside your broader energy procurement approach rather than running separately, because price, risk and carbon are linked and a decision made for one affects the others.

Catalyst helps UK businesses build renewable energy procurement strategies that hold up, from matched supply and corporate PPAs through to on-site solar. If you want power you can stand behind when a customer or auditor asks, get in touch with our team.

Related service: Energy Procurement, how Catalyst helps businesses buy power that is cleaner, smarter and easier to defend.