In This Time of Global Warming, We Now Have a Global Cooling Prize

CC BY 2.0. Lloyd Alter/ Air conditioners in Changsha, China

Big bucks go to the teams that come up with an air conditioner that's five times as good.

We have noted that as poverty decreases, air conditioning increases. In an earlier post we quoted a study that predicted that 700 million air conditioners would be added by 2030. "In terms of electricity use and greenhouse gas emissions, that’s like adding several new countries to the world."

That's why Richard Branson and others have sponsored the $2 million Global Cooling Prize, led by the Rocky Mountain Institute.

The prize will attract talent from across sectors and around the world to design a cooling solution for a typical tropical or subtropical home that will have at least 5x less climate impact. This will be achieved through a combination of dramatically reduced consumption of grid-supplied electricity and use of lower global-warming-potential refrigerant per unit of cooling than a typical RAC [room air conditioner] unit being sold in the market today.
The problem

Global Cooling Challenge/Screen capture

Branson tells Adele Peters of Fast Company that "the increase in energy consumption for cooling represents a massive risk to meeting our climate goals." The prize, he says, “can literally help save the world from the disaster it’s facing.” It can certainly help.

This technology could prevent up to 100 gigatons (GT) of CO2-equivalent emissions by 2050, and put the world on a pathway to mitigate up to 0.5 ̊C of global warming by 2100, all while enhancing living standards for people in developing countries around the globe.
impact of prize

Global Cooling Challenge/Screen capture

The prize criteria are daunting. The Rocky Mountain Institute, which prepared the document, picked a baseline unit, a 1.5 ton mini split like the kind you see hanging off every apartment building in China. The primary criterion is that the winners have five times less impact than the baseline unit, in a combination of reduced electricity demand and reduced global warming impact. "Residential cooling demand is expected to increase by 5X in developing countries over the next 30 years. A cooling solution that has 5X lower climate impact is needed to reverse the trend in increasing greenhouse gas (GHG) emissions due to this unprecedented growth in cooling demand."

The unit can't cost more than twice the baseline unit cost, cannot draw more than 700 watts at full load (seems high to me but they claim that is a 60 percent reduction from the baseline unit), cannot consume more than 14 litres of water per day (if people are trying evaporative technologies), and cannot have any onsite emissions (which knocks out gas-fired absorption units).

Units winning the competition have to be capable of keeping the temperature at about 27°C (a toasty 80+°F) at around 60 percent humidity. Seems hot, but evidently "a temperature of 27 ̊C is increasingly being used internationally as the standard indoor set point for air-conditioning ratings."

The air conditioner should not require any major changes to dwellings. "For example, the installation of the super-efficient and climate-friendly air conditioner units cannot mandate replacement of walls or major structural, electrical, or plumbing upgrades to existing multifamily apartment buildings."

Air conditioners in China

Lloyd Alter/CC BY 2.0

The trouble is, air conditioning units are often bigger than they otherwise would have been because those walls are so crappy. That is why I have written We need better air conditioners, but first we need radical building efficiency.

But an AC unit that costs just twice as much and does a fifth of the damage would be a great step forward. Combine that with radical efficiency and you've solved a major problem.