The Green Savings Bond was first launched in October 2021 at 0.65%.

The rate was doubled to 1.3% in February 2022.

The new bond - designed to encouraged investments in the ‘green economy’ - will pay 4.2% gross/AER fixed over a three-year term. The previous rate offered was 3% gross.

NS&I says savers putting money into Green Savings Bonds will help fund, “vital green projects across the UK as part of the UK Government Green Financing Framework.”

Projects will include greener transport, using renewable energy instead of fossil fuels, preventing pollution, using energy more efficiently, protecting natural resources and adapting to a changing climate.

Green Savings Bonds achieved sales of approximately £288m by 31 March 2022. Critics said the initial rates offered were too low to generate much saver interest.

The minimum investment in the bonds is £100, with a maximum of £100,000 per person for each issue. Investors need to be aged 16 or over to purchase the bonds from NS&I.

The full amount deposited will be held for three years and cannot be withdrawn during this time although there is a 30 day cooling off period at the start. Other terms available from NS&I.