Coffee is best served at 85°C — the same temperature used to accelerate endurance tests for electronics. Mere coincidence? Not if you’re a UCLA scientist developing solar cells using a promising new material. (Or a science journalist dishing up the latest dispatch from a world-leading electronic materials lab.) Taste for yourself at Spectrum …
Hawaii’s legislature voted yesterday to stake the state’s future on renewable energy. According to House Bill 623, the archipelago’s power grids must deliver 100 percent renewable electricity by the end of 2045. If the compromise bill is signed by the governor as expected, Hawaii will become the first U.S. state to set a date for the total decarbonization of its power supply. Renewable energy has been booming. Between 2008 and 2013, renewable energy jumped from 7.5 percent to 18 percent of the state’s capacity. HB623 seeks to extend and turbo-boost that trend, calling for 30 percent renewables in 2020 and 70 percent by 2030 en route to the final leap to 100 percent. That last jump could be difficult, says Peter Crouch, a power grid simulation expert and dean of engineering at the University of Hawaii’s flagship Manoa campus. “Today I don’t know whether we can do it,” he says. Continue reading “Hawaii Says ‘Aloha’ to 100% Renewable Power”
Adding energy storage to sites with rooftop solar power generation offers a range of potential benefits. A battery can help smooth out solar’s inherently variable supply of power to the local grid, and even keep buildings powered during blackouts. Consequently, power-conversion innovators are developing a host of new products designed to reduce the cost and improve the efficiency of integrated solar-storage systems.
Some analysts project a boom in the co-location of solar and energy storage. GTM Research, for example, foresees that co-located PV and storage will grow from $42 million in 2014 to more than $1 billion by 2018. However, the market is moving slower than it might thanks to a little-discussed regulatory roadblock in the United States.
According to Vic Shao, CEO for the Santa Clara, California-based energy storage startup Green Charge Networks, tightly integrating storage with photovoltaics in some key states—including Hawaii and California—runs afoul of the “net metering” rules by which PV owners earn lucrative retail rates for the surplus power they feed to the grid. Adding storage can disqualify solar systems for net metering, in which utilities can pay their owners wholesale power rates that are several times lower than retail. “That is obviously a pretty big problem for anybody considering solar. That could kill a lot of projects,” says Shao. Continue reading “Storing Solar Energy: A great idea caught on contested ground”
A partial eclipse of the sun headed for Europe next Friday has grid operators in a tizzy. On the morning of March 20 Europe’s skies will darken for the first time since solar power became a meaningful piece of some countries’ power supply, and the impact could be dramatic.
“It’s a very, very big challenge for the transmission system operators in Europe,” says Enrico Maria Carlini, Head of Electric System Engineering for National Dispatching at Rome-based Italian transmission system operator Terna.
The Brussels-based European Network for Transmission System Operators for Electricity (ENTSO-E) judges in an eclipse impact analysis released last month that it poses a, “serious challenge to the regulating capability of the interconnected power system.”
While an eclipse markedly reduced solar generation in western North America last October according to energy tracking firm Opower, Europe’s far greater levels of solar power make for bigger stakes. ENTSO-E projects that the moon’s jaunt across the sun’s path next Friday could slash more than 30 gigawatts (GW) of solar generation in Continental Europe over one hour if clouds are scarce and solar generation is high. That’s the equivalent of turning off 30 big coal or nuclear power stations. Continue reading “Solar Eclipse Will Test European Power Grids”
Since 2013, a big mainland energy firm has been raring to build Hawaii’s first inter-island power cable, arguing that only a unified power grid can enable the renewable energy developments needed to break Hawaii’s addiction to imported petroleum. Now that big outsider—Juno Beach, Florida-based NextEra Energy—is trying to absorb Hawaii’s power providers in one big bite.
In December, NextEra announced plans for a friendly $4.3 billion acquisition of Hawaiian Electric Industries, which owns the vertical monopolies that run the archipelago’s island grids (with the exception of Kauai’s). Observers debating what the acquisition would mean for Hawaii’s electrical future see at least three quite distinct outcomes:
- NextEra secures Hawaiian Electric and builds cables to unify its assets, unleashing renewable energy development
- NextEra’s bid for Hawaiian Electric is squashed by officials with longstanding mistrust of outside interests, and the island utilities proceed on their own
- NextEra wins approval for the acquisition but drops its cable ambitions, focusing instead on bringing liquefied natural gas to Hawaii to repower Oahu’s oil and coal-fired generators
Interconnecting the islands is an idea that dates all the way back to an 1881 meeting in New York City between Hawaii’s then-King Kalakaua and Thomas Edison. Kalakaua’s officials asked Edison if electricity could be generated from the Big Island’s active volcano and delivered via subsea cable to Oahu to bring electric light to Honolulu, thus sparing Hawaii greater dependence on Australian coal. Edison said the scheme could work, according to a report by the New York Sun, but demurred that it, “would cost so much, that’s all.”
134 years later, one hears essentially the same arguments for and against a unified Hawaiian grid. Proponents such as NextEra and the Hawaii State Energy Office say Oahu must hook up to its neighbors’ grids because it lacks the renewable resources needed to meet even half of its power demand—over 7,500 gigawatt-hours (GWh) per year, or nearly three-quarters of the state’s total.
Hawaii’s other islands, by contrast, have renewable potential to spare, says a 2010 analysis commissioned by the U.S. Department of Energy’s National Renewable Energy Lab. Lanai and Molokai could each generate over 1,000 GWh per year of wind power; Maui has over 2,000 GWh of viable geothermal, wind, and solar resources; and Hawai’i (better known as the Big Island) has over 6,000 GWh of geothermal potential. Sharing these resources with Oahu via subsea cables, the authors concluded, was the only way to meet Hawaii’s goal to push renewables to 70 percent of the power supply by 2030.
In 2013, NextEra proposed to start with a 180-kilometer-long, high-voltage direct current (HVDC) link between Maui and Oahu dubbed NextGrid Hawaii. Last year, Pacific Business News reported that NextEra had secured property in downtown Honolulu for the converter station where NextGrid’s pair of 200-megawatt cables would come ashore and link up with Oahu’s AC grid.
NextGrid would cost an “enormous” $600-800 million, according to Pacifc Business News, but NextEra said it would save the islands’ utilities at least $4.8 billion over its first 40 years of operation. The State Energy Office conservatively pegs net savings to consumers at a more modest $423 million, plus $128 million in environmental benefits.
One source of savings is avoided ‘curtailment’ of wind farms on Maui, which already produce more power at times than the local grid can handle. Hawaiian Electric’s Maui subsidiary ‘curtailed’ 20.6 GWh of wind generation last year. (Kauai’s utility expects to begin curtailing solar power generation this year.)
The promise of better renewable energy utilization earned NextEra support from some environmental groups. “We’re stronger together,” says Jeff Mikaluna, executive director for the Honolulu-based Blue Planet Foundation. In addition to better integrating renewables, says Mikaluna, tying the islands together should also reduce the need to keep fossil fueled power plants running in reserve.
NextGrid also appears to be spurring interest in cables to other islands, such as the Big Island. That island’s biggest landholder, the historic Parker Ranch, says a cable to Oahu could benefit a pumped hydroelectricity storage project it is developing. “Parker Ranch could enable a large-scale storage solution as part of an integrated statewide grid,” wrote Parker Ranch CEO Neil Kuyper inan August 2014 press release.
Of course, as is usually the case for transmission proposals, the idea of inter-island cables also has its critics. Some question, as Thomas Edison did, whether cables will really pencil out economically. Henry Curtis, executive director for Honolulu-based environmental advocacy group Life of the Land and a blogger on energy issues, says technical challenges associated with laying power cable over steep subsea slopes could inflate project costs.
Curtis also questions the cables’ environmental benefits, and highlights potential environmental harm. NextEra’s Maui-Oahu cable, for example, would traverse a humpback whale sanctuary.
And cables might ultimately prove unnecessary if advances in grid and power generation technologies expand Oahu’s indigenous renewable resources. Smarter inverters, for example, are helping Oahu’s grid cope with increasing levels of distributed solar energy. Curtis says more energy may be available just offshore, citing the ocean thermal energy converter currently being tested by Hawaii-based Makai Ocean Engineering.
Distributed generation advocates, meanwhile, are raising alarms about the track record of NextEra subsidiary Florida Power and Light (FPL), the utility that serves most of Florida. In December, Greentech Media noted that Florida ranks 29th in the country for overall renewable energy development, and blamed FPL for the sun-soaked state’s shortage of solar power: “It’s not for lack of sunshine; it’s lack of policy. Florida has no renewable standard—FPL has crushed every effort to establish one.”
Energy analyst William Pentland raised similar alarms in Forbes last month. “Hawaiians should think long and hard about NextEra’s track record in the Sunshine State before approving any merger,” writes Pentland.
NextEra is, for its part, playing the grid unification card close to its chest as Hawaii’s regulators weigh its offer for Hawaiian Electric. One thing appears certain: NextEra will face heightened expectations to deliver on Hawaii’s renewable energy aspirations if the acquisition goes through.
Blue Planet Foundation’s Mikaluna says Hawaiian Electric was saying what state leaders wanted to hear at the state capitol earlier this week. During a hearing on a bill proposing a 100-percent-renewables standard for Hawaii’s utilities for 2040, Hawaiian Electric’s representative abandoned the utility’s traditional tack. Rather than hedging on the prospects for zeroing-out fossil fuel consumption, the new message was ‘How about 2050?’ “That’s a first,” says Mikaluna.
This post was created for Energywise, IEEE Spectrum’s blog on green power, cars and climate
Clashing energy interests on the Japanese island of Kyushu have prompted Japan’s government to clamp down on solar power development nationwide. While the government calls it a necessary revision to assure grid stability amidst rapidly rising levels of intermittent solar energy, critics see a pro-nuclear agenda at work—one that could stunt Japan’s renewable energy potential.
Solar development in Japan has exploded since the Fukushima nuclear disaster of 2011. Thanks to an attractive feed-in tariff (FIT) program that guarantees premium rates for renewable power generation pushed through in the disaster’s aftermath, developers have since installed over 10 gigawatts of solar capacity. The solar surge marks a return to glory for the country that once dominated the global PV industry.
But Japan’s solar revival has occurred under a cloud. The pro-nuclear Liberal Democratic Party regained power in late 2012, intent on restarting idled nuclear reactors that once generated nearly one-third of Japan’s electricity. The nuclear cloud produced its first lightning bolts on Kyushu in September, and has now spread nationwide. Continue reading “Japan Seeks to Rein In a Solar Juggernaut”
Renewable energy is often intermittent, and that variability presents a variety of challenges to power grids. The nature and magnitude of the challenges depends on the time frame — from fractions of a second to seasonal or even multiyear variations — as well as the nature of the grid itself. The latter is evident in two of my articles from last week looking at how seconds-to-minutes fluctuations in solar power complicate grid controllers’ efforts to maintain alternating current at the 60 hertz frequency and the roughly 110 volt power levels required by North American devices.
Fluctuating AC frequency stars in my Technology Review dispatch from the paradise of Kauai, where the island utility is riding an electrical roller coaster as it pushes solar towards 80 percent of peak power flows Continue reading “Solar Power and Grid Stability: Scenarios and solutions”