Going 100% renewable has become a gold standard for companies and countries around the world. But despite these efforts to up wind and solar usage, global emissions continue to steadily increase.

In a recent commentary, John Woolard, a Senior Fellow in World Resources Institute’s Energy Program, argues that it’s time for consumers to shift their focus from adding more renewables to committing to 100% zero-carbon energy. Woolard recently sat down with WRI Vice President for Communications Lawrence MacDonald to talk about the most effective ways to deliver affordable, clean power to the grid and why it’s crucial to examine the carbon emissions produced per unit of electricity.

Woolard recently served as Vice President of Energy at Google, where he focused on transitioning the tech giant to 100% renewables, signing power purchase agreements with solar and wind farms to meet the company’s massive energy demand. But as the team at Google did some analysis, they came to two realizations: first, that Google’s uptick in renewables wasn’t completely eliminating its emissions, and second, that data centers run 24 hours a day, seven days a week – though the sun doesn’t shine so often. That was when Woolard realigned his strategy toward zero-carbon power that could be as clean and reliable as possible.

“The manufacturing process, industry and transportation it takes to get [goods] to your door has a massive environmental footprint behind it,” Woolard explains. “Where we use massive amounts of energy is not the residence, but across the whole economy, and majority of that still comes from fossil fuels. We need to really think about how we effectively displace coal and oil as the two largest emitters – and what drives about 78 percent of our carbon challenges in the world.”

While renewables are certainly part of the solution to these carbon challenges – it’s important to build lots of wind and solar in the near term to get to a low-carbon grid – variability and storage costs mean they may not be able to do it alone. Woolard makes the case that it’s essential to use other low-carbon power sources in order to keep the lights on sustainably at low cost.

To demonstrate his point, Woolard contrasts the energy strategies of Germany and the United Kingdom – one country that added significant renewables but ended up with high carbon emissions and high electricity prices, and one that made “carbon per unit of energy” its key metric, resulting in its global leadership in emissions reductions.

“The UK has lower carbon content in all of their electricity, and they’ve been able to do it by really focusing on getting rid of coal,” Woolard says. “They’ve used efficiency, they’ve used renewables, but they’ve also used natural gas to get rid of its coal. You don’t need to use gas all the time – just when the wind’s not blowing. That combination has been very effective at making significant progress at a much lower cost.”

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