"The world needs investments in climate infrastructure of $1 trillion per year to keep temperature rise under two degrees."

Phase Two culminated in the Paris Climate Accord, embraced by 195 nations (all but Nicaragua and Syria), and launched the current Phase Three with its focus on putting money to work to create a new era of climate infrastructure. Even though President Trump is undoing federal clean power initiatives and threatening to withdraw from the Paris Accord, Phase Three will move forward with rising global momentum.

The world needs investments in climate infrastructure – including clean energy, water, and waste-to-value – of $1 trillion per year to keep temperature rise under two degrees, according to many experts. At present, $287.5 billion per year is being invested, according to Bloomberg New Energy Finance, so we need to quadruple the current rate within five-to-seven years to have a shot. Key to success is engaging institutional investors and their more than $80 trillion in assets, by demonstrating that money can be made in the process. Fortunately, the battle is being waged on many fronts, and progress is evident.

Pension funds in Canada and Scandinavia are making healthy profits investing in wind, solar, and biomass. They have a history of doing so, a track record and results.

Nine institutional investors from five nations have committed $1.45 billion to Aligned Intermediary, an investment advisory group for climate infrastructure, which I lead. Large asset managers, including BlackRock and TPG, are beginning to offer green or impact funds. And universities are wrestling with how to invest their resources to benefit the planet.

Governments are engaged as well. Development finance institutions, including Asian and African development banks, are co-investing to encourage institutional capital. USAID and OPIC are working to ease the way for capital to move into the clean and green sectors.

State governments are increasingly active, as the regional alliances make clear. State green banks are working to overcome market obstacles, with New York having committed $1 billion to alleviate financing gaps in clean energy markets. Last month, California signed an agreement with Ontario and Québec linking their carbon markets.

For Phase Three to be successful, we must focus on three priorities:

Increase dramatically investments in solar and wind power, especially in countries and states where it is languishing. Solar power was the fastest-growing source of new energy worldwide last year, according to the International Energy Agency. Renewable energy accounted for two-thirds of new power added to the world's grids.

Bring more institutions into the climate infrastructure market, with the asset-management industry offering more funds in clean and green investments. As we have seen in other markets, such as home mortgages and consumer credit, we can accomplish this by (1) creating standardized financial products designed specifically for institutional investors, (2) establishing new investment platforms focused solely on this sector to facilitate greater institutional investment, and (3) investing in the growth of clean energy companies that are creating long-term climate infrastructure assets that institutional investors want to acquire.

Phase Three in the climate war is well underway, but we must expand the financial commitments to it in every way possible as quickly as possible. Now is the time. We cannot wait.

Commentary by Peter Davidson, co-founder and CEO of Aligned Intermediary and former executive director of the U.S. Department of Energy's Loan Programs Office.

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