How is my current renewable percentage calculated?

It is the sum of your renewable procurement — PPAs, on-site generation, and RECs — divided by your total annual electricity consumption, expressed as a percent. The tool caps renewable at total load since you cannot exceed 100% of what you consume.

What is the required annual growth rate?

It is the compound annual growth rate your renewable procurement must follow, starting from today's level, to fully cover your load by the target year, assuming flat consumption. If you procure nothing yet, a growth rate is undefined and you must simply begin.

Why does linear procurement differ from the growth rate?

Linear procurement spreads the remaining shortfall evenly across the years, giving a fixed MWh to add each year. The growth rate instead compounds off your existing base. Both are valid planning lenses; the linear figure is easier to budget while the rate shows momentum.

Do RECs count the same as PPAs under RE100?

RE100 prioritises power purchase agreements and on-site generation and applies credibility criteria to unbundled RECs. A portfolio heavy in low-quality RECs may not fully count toward the pledge, so treat the percentage as an upper bound and check RE100's technical guidance.

Does this assume my electricity use stays flat?

Yes. The calculation holds total load constant to the target year. If you expect demand to grow, your real procurement target rises, so re-run the tool with a higher projected total or revisit it annually as load changes.

What is the RE100 Renewable Energy Pledge Progress Calculator?

Enter total annual electricity consumption, renewable procurement from PPAs, on-site generation, and RECs, plus a target year, to compute current renewable percentage, annual shortfall, linear procurement needed, and the required growth rate to reach 100% RE. It runs free in your browser on Gera Tools, with nothing uploaded.

RE100 Renewable Energy Pledge Progress Calculator

Name: RE100 Renewable Energy Pledge Progress Calculator
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

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A 100% renewable electricity pledge only means something if you can show a year-on-year trajectory toward it. This calculator turns your current procurement mix and target year into a clear percentage, a shortfall, and the procurement pace you need to actually hit the goal.

How it works

The maths is straightforward but easy to get wrong by hand:

current RE %     = renewable MWh / total MWh × 100
shortfall        = total MWh − renewable MWh
years remaining  = target year − current year
linear per year  = shortfall / years remaining
required growth  = (total / current renewable)^(1/years) − 1

Renewable procurement is the sum of PPAs, on-site generation, and RECs, capped at your total load. The required growth rate is a compound annual growth rate off your existing base — if that base is zero, no rate is defined and the linear figure becomes your starting target.

Worked example

A manufacturing company consumes 120,000 MWh per year. It currently sources:

30,000 MWh from a wind PPA
8,000 MWh from rooftop solar on its warehouses
2,000 MWh from unbundled RECs

Total renewable procurement: 40,000 MWh — a 33% renewable share today. The company pledged 100% RE by 2030.

Starting from 2026 with four years remaining:

Shortfall: 80,000 MWh
Linear procurement needed: 20,000 MWh added each year
Compound growth rate off the 40,000 MWh base: roughly 32% per year

Both the linear and compound figures land at 120,000 MWh by 2030, but the compound path front-loads less procurement and back-loads more — which may or may not match what the PPA market can deliver.

Understanding the two planning lenses

Linear (equal increment each year): Easy to budget and explain to investors. You add the same fixed MWh of renewable contracts annually, regardless of what you already have. This is useful when renewable procurement costs are fairly stable and you can sign a new PPA each year.

Compound growth rate: Tells you the momentum your procurement needs. A 32% rate means each year’s procurement must be 32% larger than the previous year’s total. This is realistic when you expect to build on existing contracts with add-ons rather than fresh annual starts.

What counts under the RE100 criteria

RE100 (the campaign run by The Climate Group and CDP) sets credibility standards for what counts toward the pledge. In general:

On-site generation counts when it offsets your own consumption.
PPAs with direct connection or proxy generation that matches your hourly or annual profile count well.
Unbundled RECs / GOs count in principle but RE100 encourages higher-quality procurement — a portfolio relying entirely on cheap, old unbundled certificates may not fully satisfy voluntary reporting frameworks such as GHG Protocol Scope 2 market-based accounting.

This calculator gives you a percentage based on MWh quantities. For full compliance assessment, check RE100’s technical guidance, which sets criteria on certificate type, vintage, and country-of-origin matching.

Limitations to plan around

The calculation assumes flat electricity demand to the target year. If your business is growing or adding electrified heating, vehicles, or data-centre capacity, your real total will rise, and a fixed 120,000 MWh procurement plan will fall short. Re-run the calculator each year using updated consumption forecasts to keep your trajectory honest.