SPECTRUM: “Swarm Electrification” Powers Villages in Bangladesh

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SOLshare’s power controllers link up homes or businesses to form a DC distribution grid. Image: ME SOLshare

Bangladesh hosts the world’s largest collection of off-grid solar energy systems. Rooftop panels and batteries electrify over 4 million households and businesses there. The Dhaka-based startup ME SOLshare believes it has the technology to link these systems and foster a solar energy-sharing economy. If the company succeeds, home systems will morph into village minigrids, offering wider access to more power at lower cost.

SOLshare’s European founders—Sebastian Groh, Hannes Kirchhoff, and Daniel Ciganovic—conceived their “swarm electrification” power-sharing platform during grad-school brainstorming sessions in Germany and California. The three moved to Dhaka to define, engineer, and launch their product, starting with power measurements in off-grid solar homes.

What Groh and his cofounders discovered upon arrival in 2015 was plenty of spare power going to waste. Typically, the batteries in home systems are sized to capture the power generated during the relatively dim monsoon season. As a result, during much of the year there is extra power available that isn’t captured. On average, about 30 percent of each system’s potential output is lost.

SOLshare’s technology is designed to share this extra power.  A smart power controller, called a SOLbox, is installed in each home or business and linked with cables to other local SOLboxes to form a DC distribution grid. The SOLbox enables users to set how much power they want to share with or draw from the network, and at what price…

… READ ON AT SPECTRUM.IEEE.ORG

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SPECTRUM: Exposing the Power Vampires in Self-Driving Cars

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Drag from rooftop sensors makes Waymo’s self-driving minivan an energy hog. Photo: Wikimedia/Dllu

By driving smarter, autonomous cars have the potential to move people around and between cities with far greater efficiency. Estimates of their energy dividends, however, have largely ignored autonomous driving’s energy inputs, such as the electricity consumed by brawny on-board computers.

 

First-of-a-kind modeling published today by University of Michigan and Ford Motor researchers shows that autonomy’s energy pricetag is substantial — high enough to turn some autonomous cars into net energy losers.

“We knew there was going to be a tradeoff in terms of the energy and greenhouse gas emissions associated with the equipment and the benefits gained from operational efficiency. I was surprised that it was so significant,” says to Greg Keoleian, senior author on the paper published today in the journal Environmental Science & Technology and director of the University of Michigan Center for Sustainable Systems. Continue reading

Bomb Cyclone Exposes Perry’s Subsidy Fallacy

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Pilgrim Nuclear Power Plant: Looks good on a sunny blue sky day, but didn’t weather the storm. Photo: NRC

Extreme weather events have knocked both nuclear and coal-fired power plants offline in just the past six months, undercutting the Trump Administration’s argument that subsidizing these aging energy generators is crucial for bolstering grid stability.  The latest failure came late last week when Winter Storm Gregory forced a nuclear plant in New England offline, ratcheting up the challenge facing grid operators amidst the “bomb” cyclone’s high winds and freezing temperatures. Continue reading

Circuit Reclosers Probed as Potential Cause of California Fires

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Automatic circuit recloser generating sparks at a simulated line fault. Photo: S&C Electric

Wind-swept fires that killed more than 40 people in California in recent months have also jolted the state’s biggest utilities, Pacific Gas & Electric (PG&E) and Southern California Edison (SCE). The utilities have had to work around the clock to keep power flowing to fire-afflicted communities, even as their equipment and policies face scrutiny as potential contributors to the deadly fires. California regulatorspoliticians and trial lawyers are querying SCE and PG&E’s tree trimming and line maintenance — common culprits in prior California fires — but they are also examining a utility device that produces sparks by design: automatic circuit reclosers.

Automatic reclosers are pole-mounted circuit breakers that can quickly restore power after outages, but they can also multiply the fire risk from damaged lines. While SCE is adjusting recloser operations to reduce fire risks, PG&E’s practices are less clear. And only their neighbor to the south — San Diego Gas & Electric (SDG&E) — is tapping advanced recloser technology that is safer by design.

Reclosers make quick work of many line faults, the great majority of which result from temporary insults such as a branch striking a line or the electrocution of an unlucky squirrel. As Australian recloser manufacturer NOJA Power puts it: “Like the success of Vanilla Ice, Dexy’s Midnight Runners and Devo, most network faults are transient.” In such cases the recloser detects a power surge, momentarily interrupts electricity flow, and then automatically re-closes its contacts to restart flow down the affected line.

Reclosers usually try restarting a line 2-3 times before giving up and “locking out” a line. Sometimes multiple attempts are needed to do the job, writes NOJA Power, such as when high-temperature electrical arcing at the site of the fault burns away hung trees or tree limbs.

Under the wrong conditions, however, such arcing and ignition can obviously spark a fire. Reclosers contributed to several of Australia’s deadly Black Saturday bushfires of February 7, 2009, according to the official report of the Victorian Bushfires Royal Commission. Continue reading

Mexico Border Wall Won’t Stop Cross-border Power Push

Relations between the United States and Mexico are strained at the national level, with President Donald Trump pushing his promised border control wall and demanding a U.S.-favored rewrite of the North American Free Trade Agreement (NAFTA). But Mexico and the southwestern states have continued working towards an international agenda for electricity, and regional players are talking up a first set of projects due to be completed before Trump’s term is up — projects that put the region on a path to a far more electrically-porous border.

These projects include a trio of new crossborder links between California, Arizona and Mexico to be completed in the next three years. They also include grid studies, revised market rules, and new power lines within Mexico that could rapidly expand flows over all of the U.S.-Mexico interties. “The proposition right now is fairly small because the interconnections are small. But that’s going to change,” says Carl Zichella, director for Western transmission at the Natural Resources Defense Council. Continue reading

Solar Microgrids May Not Fix the Caribbean’s Devastated Power Systems

After the destruction inflicted across the Caribbean by hurricanes Harvey, Irma, and Maria, renewable energy advocates are calling for a rethink of the region’s devastated power systems. Rather than simply rebuilding grids that delivered mostly diesel generation via damage-prone overhead power lines, renewables advocates argue that the island grids should leapfrog into the future by interconnecting hundreds or thousands of self-sufficient solar microgrids.

“Puerto Rico will lead the way for the new generation of clean energy infrastructure. The world will follow,” asserted John Berger, CEO for Houston-based solar developer Sunnova Energy in a tweet before meeting in San Juan with Puerto Rico Governor Ricardo Rosselló this week. Rosselló appears to be on board, inviting Elon Musk via tweet to use Puerto Rico as a “flagship project” to “show the world the power and scalability” of Tesla’s technologies, which include photovoltaic (PV) rooftops and Powerwall battery systems.

Some power system experts, however, say the solar-plus-batteries vision may be oversold. They say that the pressing need to restore power, plus equipment costs and other practical considerations, call for sustained reliance on centralized grids and fossil fuels in the Caribbean. “They need to recover from the storm. Unfortunately I think the quickest way to do that is to go back to how things were before,” says Brad Rockwell, power supply manager for the Kauaʻi Island Utility Cooperative that operates one of the most renewable-heavy grids in the U.S. Continue reading

NATURE Scientists Get Political on Climate

By Peter Fairley for Nature / October 11 2017

It’s moving day at the Legislative Assembly of British Columbia on a sunny summer morning in Victoria, Canada, and climate scientist-turned politician Andrew Weaver is battling to retain an expansive leather sofa for his new basement office. Just a few weeks earlier, in May 2017, thousands of people in and around Victoria cast their votes for the British Columbia Green Party, which Weaver leads, growing the caucus from his one lonely seat to three. The wider of the office’s sofas, he explains, will be crucial during long nights of debate and voting. “This is the one you can sleep on. And we need that.”

Three seats in an 87-seat legislature might sound modest, but it’s enough to make Weaver — a professor at the University of Victoria — into a political kingmaker. The incumbent Liberal Party and the opposition New Democratic Party (NDP) each garnered fewer than half of the seats, giving Weaver’s Green Party the balance of power. Weaver exercised his new-found influence in the weeks after the election to remove Christy Clark, the Liberal premier of British Columbia, who had championed fossil fuels and neglected climate policy. He negotiated climate-friendly terms with the NDP to install John Horgan as the party’s first premier in 16 years.

Weaver is an internationally recognized pioneer of models that represent Earth’s physical systems at a modest resolution, facilitating the simulation of climate over tens of thousands of years. His ascent from academic to political power broker is a far cry from the attacks on climate scientists that are under way in the United States. But there are US researchers who dare to dream that they too can tilt the political balance. In fact, dozens have declared the intent to run for local, state or national office, promising to reverse the dismissal of climate change and other anti-science positions espoused by US President Donald Trump’s administration and other Republican Party leaders.

… READ ON AT NATURE.COM