LONDON- Barclays Bank has raised 400 million pounds ($521 million)through a green bond issuance, which will be used to finance or re-finance mortgages on energy efficent residential properties, the bank said on Wednesday.

The green bond, which matures in 2026, attracted strong institutional investor interest and was over-subscribed five times, the bank said.

Green bonds are used to finance clean energy and environmental projects such as wind farms and low-carbon transport.

The green bond is Barclays' second. The first was issued in 2017 and funded domestic residential mortgage assets.

($1 = 0.7673 pounds)

(Reporting by Nina Chestney; Editing by Kim Coghill) ((nina.chestney@thomsonreuters.com; +44 (0) 020 7513 5674; Reuters Messaging: nina.chestney.thomsonreuters.com@reuters.net))