In a recent online chat, an expert panel tackled the huge topic of how to grow investment in renewables as part of a transition to a low carbon economy. Here are 10 key lessons from the discussion:

1. Solar and wind are cheaper than you think!

Despite an investor assumption that renewables are expensive, "this stuff is really cheap", said Bloomberg New Energy Finance's Jenny Chase. There are plenty of places where solar and wind already make economic sense, provided investment conditions are right.

People will start buying solar panels for their houses - without the need for subsidies - because it makes financial sense, Chase said. Panels now sell for less than a quarter of their 2008 price. And they won't be restricted to rooftops: Solar and wind plants are increasingly feeding into the grid and fulfilling the energy needs of large local power users, such as factories, in India and Chile.

Bloomberg estimates that the world will have 600GW of photovoltaic solar worldwide by 2020 (an increase from about 150GW today) and 1,900GW by 2030; making up 5-7% of the global electricity mix. These positive predictions are based on the falling prices of renewables.

2. Policy uncertainty is the biggest obstacle to investment in renewables

Governments are failing to take up the challenge and lead the way on renewables. The energy debate has become too politicised, argued EY's Ben Warren, and a lack of cohesive and stable policy has undermined a "long-term view on investment in renewable energy". Among the problems are skewed tax relief, fossil fuel subsidies and retroactive changes to renewable incentives, which make them risky to investors, panelists said.

Politicians are also listening to the wrong people, said Bruce Davis of Abundance Generation. The increasingly vocal lobbying of those with vested interests in slowing the growth of renewables is being heard more than the majority of voters who are in favour.

3. Regulators are getting better, although they still have 'sharp teeth'

That said, panelists were positive about the role of regulators, at least in the UK. Davis, who runs crowdfunding organisation Abundance Generation, said he is constantly updating the Financial Conduct Authority about innovations and the benefits crowdfunding can bring to investors without compromising investor protections.

"There is a world of difference between the old [Financial Services Authority] and the new FCA approach," he said. "That is not to say they don't have sharp teeth, but they do make efforts to listen to evidence and form policy based on real experiences of platforms."

4. Germany, Denmark and South Africa are good role models on renewables

Germany and Denmark have made great strides on renewables - partly because they have a diverse and large ownership base, said Co-operative Energy's Paul Monaghan. Germany has over 800 renewable energy co-operatives and the government has made - and stuck to - strong incentives for renewables, while in Denmark, communities have the right to invest and profit from wind turbine programs, which creates a broad political base for policy support.

The South African government has also done well on getting the best prices. It held a competitive tender, asking a simple question: "who wants to sell us wind and solar power for the lowest prices?" It was a simple but effective strategy that was clearly aligned with the long-term goals of government and also creates sustainable jobs locally, Davis said.

5. Business is leading the way

Corporates and individuals are taking the lead and hoping that policy will eventually follow. Business interruption risk and price volatility mean that an increasing number of businesses are taking a strategic approach to energy procurement. "Direct procurement of renewable energy might just prove to be one way for the sector to reduce its dependence on government policy," Warren said.

Software company SAP's Will Ritzrau said of his company's policy: "we look at renewables as a long term approach to control our energy cost and thus margin impact."

6. We need a diversity of projects

Having as many models as possible, from small-scale initiatives to large-scale projects, will be the key to financing the necessary energy transition, Emma Howard Boyd said.

According to Davis, co-operatives are good models where there is a motivated community with the requisite time and expertise. But it's also important to have schemes that appeal to commercial developers and make them more open to community involvement.

7. The public are up for renewables

Poll after poll shows that people have bought into the idea of renewables, Monghan said; now we have to unlock the big institutional investors. Crowdfunding can provide an easy way for people to get involved in projects that have already been vetted and will offer reasonable returns. Plus, organisations such as Share Action and Divestment are helping people have control over where their money is invested.

8. Developing countries could spearhead innovation

We may well see the flow of innovation reverse, with developed markets being disrupted by companies from developing markets. Energy innovation using mobile technology is one clear example of where this could happen: "more people in India own mobile phones than they do toothbrushes", Ashden's Chhavi Sharma said.

Sharma pointed to innovations such as M-PESA, which have allowed the renewable energy sector to leapfrog in Africa. Enterprises such as Off.Grid:Electric are using a service-based model and selling pay-as-you-go solar that can be paid for daily using mobile money, akin to setting up a micro-utility.

9. Power of the internet

It's hard to imagine how crowdfunding would work in an internet-free world, Chase said. The "internet of things" and broadband availability will enable automated and smart energy consumption. Large amounts of information will be needed to make the energy markets work. Soon smart technology will control various appliances so your fridge will stop cooling if the power price spikes, and other devices can be switched on or off automatically according to need.

Social media - and the internet more generally - have the potential to accelerate the awareness and acceptance of new technology. New and viable ideas, especially if they benefit individuals, will survive and grow. However, growing into a conservative market too early is also risky and some big companies may be a little more cautious about adopting potentially too-radical innovation.

10. There's some way to go

There have been leaps and bounds in terms of innovation and affordability, which have helped renewables to become an attractive investment opportunity. But if we are to reach the kind of levels required for a genuine energy transition, there's much more to be done. Investors should continue to view opportunities realistically, but also remain open-minded enough to recognise - and tap - the great renewable opportunities that exist.

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