The growth in ethical investments is a trend that is set to continue, according to the chief investment officer with Appian Asset Management.

Historically, responsible investment was about choosing areas of the market you did not want to be in, such as tobacco or alcohol. The change that is currently happening in the markets is investors are actively seeking to make investments that have positive impacts on society and the environment.

"We have launched an Appian impact fund, and we've said to ourselves: there's a €26 trillion opportunity in positive investments over the next couple of decades in areas like water sustainability, food sustainability, resource efficiency and recycling," explained Niall Dineen. "I think investors can actually have a positive impact on society, and get a positive financial return as well if they truly embrace real impact investing."

"We genuinely believe it's possible today to find good investments in impact areas. We don't believe you have to sacrifice the financial return to actually feel your investments are having a positive impact on society and the environment."

The chief investment officer said there is still money to be made in so-called dirty investments like fossil fuels. "Oh there is, and I think it is really up to investors to choose themselves what type of investment product they want to be in. We're finding today, a lot of our clients are moving away from wanting to be associated with tobacco and oil, and they genuinely want to be invested in these positive areas for themselves, and also for their children."

Mr Dineen said over the next decade we're going to see real growth in positive investing. "I don't think it is stopping for the next couple of decades," he said.

More and more companies are highlighting their green credentials when publishing their financial results. Mr Dineen said this is aimed at both customers and investors.

"I think customers like the story, some investors like the story, but our belief is if you really want to impact fund, you have to say to yourself, 'what other companies are having a positive impact?' We have to get away from this idea that an oil company is getting better so that's where you want to invest. If you want to true impact fund, you shouldn't have any airlines or any oil stocks," he said.