By one measure – and measuring this sort of thing can get pretty complicated – the world’s biggest energy providers got a whole lot greener in 2013.
The publication EI New Energy, in releasing its third annual compilation of the “Top 100 Green Utilities” (PDF), said emissions-free sources accounted for 80 percent of the new energy generating capacity added by large utilities in 2013, a dramatic increase from 30 percent the year before.
The big additions – 21 gigawatts of non-hydropower renewables, 16 GW of hydro, and 3 GW of nuclear power – didn’t jumble the leaderboard much, at least not at the top: the Spanish company Iberdrola heads the new list, as it did in 2013, followed again by Energias de Portugal. The only changes in the top 10 came with companies swapping places, as China General Nuclear moved up to third ahead of NextEra Energy, and E.On nudged aside Berkshire Hathaway Energy for the No. 9 spot.
The case of China General Nuclear, China’s biggest nuclear power operator and developer, highlights the considerations and conundrums that arise when assigning a “green” rating to energy sector players.
EI New Energy scores companies on three criteria, each of which carries equal weight in the rankings: the amount of carbon dioxide per megawatt-hour of electricity generated, termed “emissions intensity”; the percentage of renewable energy capacity among owned generating plants; and the volume of renewable energy capacity owned. So having lots of nuclear power and big hydropower – not considered green by everyone’s standards – can benefit a company by improving its carbon intensity. However, EI New Energy doesn’t count those sources as “renewable,” so they will get a utility only so far in the rankings.
The case of China General Nuclear illustrates how this can play out. The company has 18.6 gigawatts of generating capacity, of which 11.6 GW is nuclear, 1.5 GW hydro, and 5.5 GW a combination of wind and solar, according to EI New Energy. That means its emissions intensity is zero, earning the company a top rating and the maximum 100 points in that category. On renewables, only the 5.5 GW of wind and solar counts, but that’s still 30 percent of the company’s portfolio, and 83 percent of category leader Energias de Portgugal’s 36 percent renewables – earning China General Nuclear 83 more points. Finally, on renewable energy volume, the 5.5 GW is 29 percent of China Guodian’s category-leading 18.7 GW, earning China General Nuclear 29 more points.
Iberdrola takes a different path to the top. Unlike China General Nuclear, it has emissions in its portfolio (it doesn’t crack the top 20 in the carbon intensity category). But with a massive wind power portfolio – including more than 5 GW in the United States – most of Iberdrola’s emissions-free sources count as renewable energy, and it racks up big points for percentage and volume of renewables.
Among U.S. companies, No. 4 NextEra Energy earns its high ranking through a combination of nuclear and wind power; its 10.2 GW of wind make up around 15 percent of total U.S. wind power capacity. No. 10 Berkshire Hathaway Energy is another big wind player through its collection of companies, which includes a number of electrical utilities around the country.
One of those Berkshire Hathaway companies, the recently acquired NV Energy, finished first earlier this year in a U.S.-focused study that ranked electric utilities by renewable electricity sales as a percentage of all retail electric sales (21.08 percent). Unlike the EI New Energy report, this method included renewable energy that the utilities also bought through power purchase agreements,not just the stuff that came from plants they owned. Other leaders in that study (PDF), carried out by Ceres in partnership with Clean Edge, were Xcel Energy (18.11 percent renewables), PG&E (16.87 percent), Sempra Energy (16.86 percent) and Edison International (16.67 percent).
One more note about the EI New Energy rankings: Not every big company that might commonly be thought of as an electrical utility is included. For instance, the report notes that “some large utilities in terms of sales, such as New York’s Con Edison, are not included, as they only supply power without generating it.” Still, the ranked companies cover a lot of ground; EI New Energy said “that top 100 companies represent almost 60 percent of the world’s power generating capacity.”