Companies could issue a record $30 billion in so-called "green bonds" this year, but further growth in the market will depend on developments in China and common standards, Standard & Poor's Rating Services said on Monday.

Proceeds from green bonds are typically used on projects to cut greenhouse gas emissions, adapt to climate change, increase energy efficiency or expand the use of renewable energy.

The bonds are mainly issued by development banks and corporates such as utilities and real estate companies.

The green bond market as a whole has been growing, with issuance tripling in last year to $36.6 billion. Corporate issuance accounted for around $19 billion.

This year, the corporate market has been boosted by more issuances, including Danish wind turbine manufacturer Vestas' (VWS.CO) seven-year 500 million euro ($544 million) bond earlier this month and French recycling company Peprec's 480 million euro bond.

"We expect green bond issuance to remain relatively buoyant given investor appetite for green products as well as issuers taking advantage of the exceptional demand," S&P said in a statement.

"The surge in green bond sales represents growing demand among investors for green investments amid concerns about climate change," it added.

However, commonly agreed standards on what constitutes a green bond and transparency over how proceeds are used will be needed to make the market become more mainstream.

The corporate green bond market could experience substantial growth in China this year, as the Chinese government tackles pollution and could encourage companies to raise funds by bond issuance to help diversify credit risk in the banking system, S&P said.

Declining oil prices should not hinder growth in the green bond market as price movements will have less impact on renewables than many fear due to climate change being a long-term driver for investments, S&P added.