Money talks, but nature may have the last word if climate change continues to unfold at current rates.

The World Economic Forum (WEF) recently calculated that transitioning to a sustainable, carbon-neutral future would take $13.5 trillion in investment globally between now and 2050. It’s a monumental figure, yet if industries like production, energy and transport can’t be transformed, the true cost for humanity could be much higher.

Tracking developments in this transition is all part of the job for WEF President Børge Brende. CNN spoke with him last weekend at the Doha Forum, an annual gathering of high-level diplomats and policymakers in the Qatari capital, for a temperature check on the century’s biggest challenge.

The following interview has been edited for length and clarity.

CNN: What are some of the challenges that come with transitioning to a green economy and do the benefits outweigh those challenges? 

Børge Brende: There is no doubt that the cost of inaction far exceeds the cost of action when it comes to climate change. So we do have to act, but there’s also a big energy transition taking place and there are several challenges at the same time.

There’s energy poverty – 800 million people don’t have access to electricity – there’s energy security, and then there’s a decoupling of growth in energy and CO2 emissions.

Is the Middle East headed in the right direction? What does this mean for the future? 

Decarbonization has started in the Middle East. Some of the biggest solar plants in the world are being installed and established here in the Middle East, and especially in the GCC countries (United Arab Emirates, Bahrain, Saudi Arabia, Oman, Qatar and Kuwait).

Renewables will play a very important role in the energy transition that we will hopefully see in the coming decade. Also the price of renewables is falling dramatically ­– solar power has fallen to one-tenth of the price in a decade, so that makes it also very competitive.

Should events like this be considered an opportunity for sustainable development and economic growth?

This event also focuses on the energy transition, and Qatar is a major exporter of liquid natural gas. We know that gas emits half (the carbon emissions) coal does. So in the energy transition, natural gas can also in many countries be a bridge between heavily emitting fossil fuels to a renewables-based society.