Stretching wire generates current

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Researchers at Georgia Tech have developed a new type of electric power generator able to produce AC current through cyclical stretching and releasing of zinc oxide wires. The new “flexible charge pump” generator is the fourth generation of devices designed to produce electrical current by using the piezoelectric properties of zinc oxide structures to harvest mechanical energy from the environment.

“The flexible charge pump offers yet another option for converting mechanical energy into electrical energy,” says Zhong Lin Wang, director of the Center for Nanostructure Characterization at the Georgia Institute of Technology. The generator can produce an oscillating output voltage of up to 45 millivolts. To boost the current produced, arrays of the flexible charge pumps could be constructed and connected in series. Multiple layers of the generators could also be stacked to form modules that could be implanted in the human body to power blood pressure sensors or other devices.

When the modules are mechanically stretched and released, the zinc oxide material generates a piezoelectric potential that alternately builds up and then is released. The wires are encapsulated in a flexible plastic substrate with two bonded ends; a Schottky barrier controls the alternating flow of electrons, and the piezoelectric potential is the driving force of the charge pump.

To measure generated electric energy in tests, researchers subjected the substrate and attached zinc oxide wires to periodic mechanical bending created by a motor-driven mechanical arm. Bending induces tensile strain, which creates a piezoelectric potential field along the laterally packaged wires. That in turn drives a flow of electrons into an external circuit, creating the alternating charge and discharge cycle – and corresponding current flow. Wang envisions a family of small-scale generators enabling development of a new class of self-powered wireless sensing systems that could gather, store, and transmit information without an external power source.

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As New Zealand gets serious about climate change, can electricity replace fossil fuels in time?

New Zealand Energy Transition will electrify transport and industry with renewables, grid-scale solar, wind farms, geothermal, batteries, demand response, pumped hydro, and transmission upgrades to manage dry-year risk and winter peak loads.

 

Key Points

A shift to renewables and smart demand to decarbonise transport and industry while ensuring reliable, affordable power.

✅ Electrifies transport and industrial heat with renewables

✅ Uses demand response, batteries, and pumped hydro for resilience

✅ Targets 99%+ renewable supply, managing dry-year and peak loads

 

As fossil fuels are phased out over the coming decades, the Climate Change Commission (CCC) suggests electricity will take up much of the slack, aligning with the vision of a sustainable electric planet powering our vehicle fleet and replacing coal and gas in industrial processes.

But can the electricity system really provide for this increased load where and when it is needed? The answer is “yes”, with some caveats.

Our research examines climate change impacts on the New Zealand energy system. It shows we’ll need to pay close attention to demand as well as supply. And we’ll have to factor in the impacts of climate change when we plan for growth in the energy sector.

 

Demand for electricity to grow
While electricity use has not increased in NZ in the past decade, many agencies project steeply rising demand in coming years. This is partly due to both increasing population and gross domestic product, but mostly due to the anticipated electrification of transport and industry, which could result in a doubling of demand by mid-century.

It’s hard to get a sense of the scale of the new generation required, but if wind was the sole technology employed to meet demand by 2050, between 10 and 60 new wind farms would be needed nationwide.

Of course, we won’t only build wind farms, as renewables are coming on strong and grid-scale solar, rooftop solar, new geothermal, some new small hydro plant and possibly tidal and wave power will all have a part to play.

 

Managing the demand
As well as providing more electricity supply, demand management and batteries will also be important. Our modelling shows peak demand (which usually occurs when everyone turns on their heaters and ovens at 6pm in winter) could be up to 40% higher by 2050 than it is now.

But meeting this daily period of high demand could see expensive plant sitting idle for much of the time (with the last 25% of generation capacity only used about 10% of the time).

This is particularly a problem in a renewable electricity system when the hydro lakes are dry, as hydro is one of the few renewable electricity sources that can be stored during the day (as water behind the dam) and used over the evening peak (by generating with that stored water).

Demand response will therefore be needed. For example, this might involve an industrial plant turning off when there is too much load on the electricity grid.

 

But by 2050, a significant number of households will also need smart appliances and meters that automatically use cheaper electricity at non-peak times. For example, washing machines and electric car chargers could run automatically at 2am, rather than 6pm when demand is high.

Our modelling shows a well set up demand response system could mitigate dry-year risk (when hydro lakes are low on water) in coming decades, where currently gas and coal generation is often used.

Instead of (or as well as) having demand response and battery systems to combat dry-year risk, a pumped storage system could be built. This is where water is pumped uphill when hydro lake inflows are plentiful, and used to generate electricity during dry periods.

The NZ Battery project is currently considering the potential for this in New Zealand, and debates such as whether we would use Site C's electricity offer relevant lessons.

 

Almost (but not quite) 100% renewable
Dry-year risk would be greatly reduced and there would be “greater greenhouse gas emissions savings” if the Interim Climate Change Committee’s (ICCC) 2019 recommendation to aim for 99% renewable electricity was adopted, rather than aiming for 100%.

A small amount of gas-peaking plant would therefore be retained. The ICCC said going from 99% to 100% renewable electricity by overbuilding would only avoid a very small amount of carbon emissions, at a very high cost.

Our modelling supports this view. The CCC’s draft advice on the issue also makes the point that, although 100% renewable electricity is the “desired end point”, timing is important to enable a smooth transition.

Despite these views, Energy Minister Megan Woods has said the government will be keeping the target of a 100% renewable electricity sector by 2030.

 

Impacts of climate change
In future, the electricity system will have to respond to changing climate patterns as well, becoming resilient to climate risks over time.

The National Institute of Water and Atmospheric Research predicts winds will increase in the South Island and decrease in the far north in coming decades.

Inflows to the biggest hydro lakes will get wetter (more rain in their headwaters), and their seasonality will change due to changes in the amount of snow in these catchments.

Our modelling shows the electricity system can adapt to those changing conditions. One good news story (unless you’re a skier) is that warmer temperatures will mean less snow storage at lower elevations, and therefore higher lake inflows in the big hydro catchments in winter, leading to a better match between times of high electricity demand and higher inflows.

 

The price is right
The modelling also shows the cost of generating electricity is not likely to increase, because the price of building new sources of renewable energy continues to fall globally.

Because the cost of building new renewables is now cheaper than non-renewables (such as coal-fired plants), investing in carbon-free electricity is increasingly compelling, and renewables are more likely to be built to meet new demand in the near term.

While New Zealand’s electricity system can enable the rapid decarbonisation of (at least) our transport and industrial heat sectors, international efforts like cleaning up Canada's electricity underline the need for certainty so the electricity industry can start building to meet demand everywhere.

Bipartisan cooperation at government level will be important to encourage significant investment in generation and transmission projects with long lead times and life expectancies, as analyses of climate policy and grid implications underscore in comparable markets.

Infrastructure and markets are needed to support demand response uptake, as well as certainty around the Tiwai exit in 2024 and whether pumped storage is likely to be built.

Our electricity system can support the rapid decarbonisation needed if New Zealand is to do its fair share globally to tackle climate change.

But sound planning, firm decisions and a supportive and relatively stable regulatory framework are all required before shovels can hit the ground.

 

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Omnidian Acquires Australia's Solar Service Guys to Expand Global Reach

Omnidian Acquisition of Solar Service Guys accelerates global expansion in renewable energy, enhancing solar maintenance and remote monitoring across Australia and the U.S., boosting performance management, uptime, and ROI for residential and commercial systems.

 

Key Points

Omnidian acquired Solar Service Guys to expand in Australia, unifying O&M and monitoring to boost solar performance.

✅ Expands Omnidian into Australia's high-adoption solar market.

✅ Integrates largest Aussie solar service network for O&M scaling.

✅ Enhances remote monitoring, uptime, and ROI for PV owners.

 

In a strategic move aimed at boosting its presence in the global renewable energy market, Seattle-based Omnidian has announced the acquisition of Australia's Solar Service Guys. This acquisition marks a significant step in Omnidian's expansion into Australia, one of the world’s leading solar markets, and is expected to reshape the landscape of solar panel services both in the U.S. renewables market and abroad.

Founded in 2018, Omnidian is a rapidly growing startup that specializes in managing the performance of solar power systems, ensuring they continue to operate efficiently and effectively. The company provides maintenance services for both residential and commercial solar installations, including in Washington where Avista's largest solar array highlights growing scale, and its proprietary software remotely monitors solar systems to identify any performance issues. By quickly addressing these problems, Omnidian helps customers maximize the energy output of their systems, reducing downtime and increasing the return on investment in solar power.

The company’s acquisition of Solar Service Guys, Australia’s largest solar service network, is a clear indication of its ambition to dominate the renewable energy sector globally, amid consolidation trends like TotalEnergies' VSB acquisition across Europe, that signal accelerating scale. The Australian company, which has been operational since 2006, has built a strong reputation for providing high-quality solar panel services across the country. By integrating Solar Service Guys into its operations, Omnidian plans to leverage the Australian company’s deep industry expertise and established network to extend its service offerings into Australia’s solar market.

The acquisition could not come at a better time. Australia, with its vast sun-drenched landscapes, is one of the world’s leaders in solar energy adoption per capita, even as markets like Canada's solar lag persist by comparison. The country has long been at the forefront of renewable energy development, and this acquisition presents a significant opportunity for Omnidian to tap into a booming market where solar power is increasingly seen as a primary energy source.

With the deal now finalized, Solar Service Guys will operate as a fully integrated subsidiary of Omnidian. The merger will not only strengthen Omnidian’s service capabilities but will also enhance its ability to provide comprehensive solutions to solar system owners, ensuring their panels perform at peak efficiency over their lifetime. This is particularly important as solar energy continues to grow in popularity, with more residential and commercial properties opting for solar installations as a means to lower energy costs and reduce their carbon footprints.

The acquisition also underscores the growing importance of solar energy maintenance services. As the adoption of solar panels continues to rise globally, including in Europe where demand for U.S. solar gear is strengthening, the need for ongoing monitoring and maintenance is becoming increasingly vital. Solar energy systems, while relatively low-maintenance, do require periodic checks to ensure they are functioning optimally. Omnidian’s software-based approach to remotely detecting performance issues allows the company to quickly identify and address potential problems before they become costly or result in significant energy loss.

By expanding its reach into Australia, Omnidian can now offer its services to an even broader customer base, positioning itself as a key player in the renewable energy market. The Australian solar market is projected to continue its growth trajectory, with many homeowners and businesses in the country looking to make the switch to solar power in the coming years.

In addition to expanding its geographic footprint, Omnidian’s acquisition of Solar Service Guys aligns with its broader mission to support the global transition to renewable energy. As governments worldwide push for cleaner energy alternatives and new projects like a U.S. clean energy factory accelerate domestic supply chains, companies like Omnidian are playing an essential role in making solar power a more reliable and sustainable option for consumers.

With the backing of Solar Service Guys’ extensive network and experience, Omnidian is poised to deliver even greater value to its customers, as industry transactions like Canadian Solar's plant sale underscore active market realignment. The acquisition will also help the company strengthen its technological capabilities, improve its service offerings, and accelerate its mission to create a more sustainable energy future.

As Omnidian continues to grow, the company’s success will likely serve as a model for other startups in the renewable energy sector. By focusing on performance management, expanding its service offerings, and leveraging cutting-edge technology, Omnidian is well-positioned to lead the way in the next generation of solar energy solutions. The future looks bright for Omnidian, and with this acquisition, it is well on its way to becoming a dominant force in the global solar market.

Omnidian’s acquisition of Solar Service Guys marks a significant milestone in the company’s quest to revolutionize the renewable energy industry. By expanding into Australia and enhancing its service capabilities, Omnidian is not only strengthening its position in the market but also contributing to the global push for cleaner, more sustainable energy solutions. As the world continues to embrace solar power, companies like Omnidian will be essential in ensuring that solar systems operate at peak efficiency, helping customers maximize the benefits of their investment in renewable energy.

 

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Egypt's renewable energy to reach 6.6 GW by year-end

Egypt Renewable Energy Expansion targets solar and wind power projects to diversify the energy mix, adding 6.6 GW by 2020 and reaching 8,200 MW, with UK cooperation, grid upgrades, and investment in the electricity sector.

 

Key Points

A plan to boost solar and wind by 6.6 GW by 2020, reaching 8,200 MW and diversifying Egypt's energy mix.

✅ Adds 6.6 GW by 2020; targets 8,200 MW total capacity

✅ Focus on solar, wind, grid upgrades, and investment

✅ UK-Egypt cooperation in electricity sector projects

 

Egypt is planning to expand into renewable energy projects in a bid to increase its contribution to the energy mix, in step with global records being set in renewables, and amid Saudi Arabia’s 60 GW drive in the region, the country’s minister of electricity and renewable energy Mohamed Shaker said.

Renewable power is expected to add 6.6 gigawatts (GW) by the end of 2020, a scale comparable to Saudi wind expansion underway, with plans to reach 8,200 megawatts (MW) after the completion of the renewable energy projects currently under consideration, reflecting gains seen since IRENA’s 2016 record year for renewables, Shaker added in a statement on Tuesday, even as regional challenges persist.

This came during the minister’s video-conference meeting with the British ambassador to Egypt Geoffrey Adams to explore the potential means for cooperation between the two countries in the electricity sector, including lessons from the UK project backlog now affecting investments and from Ireland’s green-electricity goals being pursued.

 

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Metering Pilot projects may be good example for Ontario utilities

Ontario Electricity Pricing Pilot Projects explore alternative rates beyond time-of-use, with LDCs and the Ontario Energy Board testing dynamic pricing, demand management, smart-meter billing, and residential customer choice to enhance service and energy efficiency.

 

Key Points

Ontario LDC trials testing alternatives to time-of-use rates to improve billing, demand response, and efficiency.

✅ Data shared across LDCs and Ontario Energy Board provincewide

✅ Tests dynamic pricing, peak/off-peak plans, demand management

✅ Insights to enhance customer choice, bills, and energy savings

 

The results from three electricity pilot projects being offered in southern Ontario will be valuable to utility companies across the province.

Ontario Energy Minister Glenn Thibeault was in Barrie on Tuesday to announce the pilot projects, which will explore alternative pricing plans for electricity customers from three different utility companies, informed by the electricity cost allocation framework guiding rate design.

"Everyone in the industry is watching to see how the pilots deliver.", said Wendy Watson, director of communications for Greater Sudbury Utilities.

"The data will be shared will all the LDCs [local distribution companies] in the province, and probably beyond...because the industry tends to share that kind of information."

Most electricity customers in the province are billed using time-of-use rates, including options like the ultra-low overnight rates that lower costs during off-peak periods, where the cost of electricity varies depending on demand.

The Ontario Energy Board said in a media release that the projects will give residential customers more choice in how much they pay for electricity at different times, reflecting changes for Ontario electricity consumers that expand plan options.

Pilot projects can help improve service

Watson says these kinds of projects give LDCs the chance to experiment and explore new ways of delivering their service, including demand-response initiatives like the Peak Perks program that encourage conservation.

"Any pilot project is a great way to see if in practice if the theory proves out, so I think it's great that the province is supporting these LDCs," she says.

GSU recently completed its own pilot project, the Home Energy Assessment and Retrofit (HEAR) program, which focused on customers who use electric baseboards to heat their homes, amid broader provincial support for electric bills to ease costs."We installed some measures, like programmable thermostats and a few other pieces of equipment into their house," Watson says. "We also made some recommendations about other things that they could do to make their homes more energy efficient."

At the end of the program, GSU provided customers with a report so that they could the see the overall impact on their energy consumption.

Watson says a report on the results of the HEAR program will be released in the near future, for other LDCs interested in new ways to improve their service.

"We think it's incumbent on every LDC...to see what ideas that they can come up with and get approved so they can best serve their customers."

 

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How Electricity Gets Priced in Europe and How That May Change

EU Power Market Overhaul targets soaring electricity prices by decoupling gas from power, boosting renewables, refining price caps, and stabilizing grids amid inflation, supply shocks, droughts, nuclear outages, and intermittent wind and solar.

 

Key Points

EU plan to redesign electricity pricing, curb gas-driven costs, boost renewables, and protect consumers from volatility.

✅ Decouples power prices from marginal gas generation

✅ Caps non-gas revenues to fund consumer relief

✅ Supports grid stability with storage, demand response, LNG

 

While energy prices are soaring around the world, Europe is in a particularly tight spot. Its heavy dependence on Russian gas -- on top of droughts, heat waves, an unreliable fleet of French nuclear reactors and a continent-wide shift to greener but more intermittent sources like solar and wind -- has been driving electricity bills up and feeding the highest inflation in decades. As Europe stands on the brink of a recession, and with the winter heating season approaching, officials are considering a major overhaul of the region’s power market to reflect the ongoing shift from fossil fuels to renewables.

1. How is electricity priced? 
Unlike oil or natural gas, there’s no efficient way to save lots of electricity to use in the future, though projects to store electricity in gas pipes are emerging. Commercial use of large-scale batteries is still years away. So power prices have been set by the availability at any given moment. When it’s really windy or sunny, for example, then more is produced relatively cheaply and prices are lower. If that supply shrinks, then prices rise because more generators are brought online to help meet demand -- fueled by more expensive sources. The way the market has long worked is that it is that final technology, or type of plant, needed to meet the last unit of consumption that sets the price for everyone. In Europe this year, that has usually meant natural gas. 

2. What is the relationship between power and gas? 
Very close. Across western Europe, gas plants have been a vital part of the energy infrastructure for decades, with Irish price spikes highlighting dispatchable power risks, fed in large part by supplies piped in from Siberia. Gas-fired plants were relatively quick to build and the technology straightforward, at least compared with nuclear plants and burns cleaner than coal. About 18% of Europe’s electricity was generated at gas plants last year; in 2020 about 43% of the imported gas came from Russia. Even during the depths of the Cold War, there’d never been a serious supply problem -- until the relationship with Russia deteriorated this year after it invaded Ukraine. Diversifying away from Russia, such as by increasing imports of liquefied natural gas, requires new infrastructure that takes a lot of time and money.

3. Why does it work this way? 
In theory, the relationship isn’t different from that with coal, for example. But production hiccups and heatwave curbs on plants from nuclear in France to hydro in Spain and Norway significantly changed the generation picture this year, and power hit records as plants buckled in the heat. Since coal-fired and nuclear plants are generally running all the time anyway, gas plants were being called upon more often -- at times just to keep the lights on as summer temperatures hit records. And with the war in Ukraine resulting in record gas prices, that pushed up overall production costs. It’s that relationship that has made the surging gas price the driver for electricity prices. And since the continent is all connected, it has pushed up prices across the region. The value of the European power market jumped threefold last year, to a record 836 billion euros ($827 billion today).

4. What’s being considered? 
With large parts of European industry on its knees and households facing jumps in energy bills of several hundred percent, as record electricity prices ripple through markets, the pressure on governments and the European Union to intervene has never been higher. One major proposal is to impose a price cap on electricity from non-gas producers, with the difference between that and the market price channeled to relief for consumers. While it sounds simple, any such changes would rip up a market design that’s worked for decades and could threaten future investments because of unintended consequences.


5. How did this market evolve?
The Nordic region and the British market were front-runners in the 1990s, then Germany followed and is now the largest by far. A trader can buy and sell electricity delivered later on same day in blocks of an hour or even down to 15-minute periods, to meet sudden demand or take advantage of price differentials. The price for these contracts is decided entirely by the supply and demand, how much the wind is blowing or which coal plants are operating, for example. Demand tends to surge early in the morning and late afternoon. This system was designed when fossil fuels provided the bulk of power. Now there are more renewables, which are less predictable, with wind and solar surpassing gas in EU generation last year, and the proposed changes reflect that shift. 

6. What else have governments done?
There are also traders who focus on longer-dated contracts covering periods several years ahead, where broader factors such as expected economic output and the extent to which renewables are crowding out gas help drive prices. This year’s wild price swings have prompted countries including Germany, Sweden and Finland to earmark billions of euros in emergency liquidity loans to backstop utilities hit with sudden margin calls on their trading.

 

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New England Emergency fuel stock to cost millions

Inventoried Energy Program pays ISO-NE generators for fuel security to boost winter reliability, with FERC approval, covering fossil, nuclear, hydropower, and batteries, complementing capacity markets to enhance grid resilience during severe cold snaps.

 

Key Points

ISO-NE program paying generators to hold fuel or energy reserves for emergencies, boosting winter reliability.

✅ FERC-approved stopgap for 2023 and 2024 winter seasons

✅ Pays for on-site fuel or stored energy during cold-trigger events

✅ Open to fossil, nuclear, hydro, batteries; limited gas participation

 

Electricity ratepayers in New England will pay tens of millions of dollars to fossil fuel and nuclear power plants later this decade under a program that proponents say is needed to keep the lights on during severe winters but which critics call a subsidy with little benefit to consumers or the grid, even as Connecticut is pushing a market overhaul across the region.

Last week the Federal Energy Regulatory Commission said ISO-New England, which runs the six-state power grid, can create what it calls the Inventoried Energy Program or IEP. This basically will pay certain power plants to stockpile of fuel for use in emergencies during two upcoming winters as longer-term solutions are developed.

The federal commission called it a reasonable short-term solution to avoid brownouts which doesn’t favor any given technology.

Not all agree, however, including FERC Commissioner Richard Glick, who wrote a fiery dissent to the other three commissioners.

“The program will hand out tens of millions of dollars to nuclear, coal and hydropower generators without any indication that those payments will cause the slightest change in those generators’ behavior,” Glick wrote. “Handing out money for nothing is a windfall, not a just and reasonable rate.”

The program is the latest reaction by ISO-NE to the winter of 2013-14 when New England almost saw brownouts because of a shortage of natural gas to create electricity during a pair of week-long deep freezes.

ISO-New England says the situation is more critical now because of the possible retirement of the gas-fired Mystic Generating Station in Massachusetts. As with closed nuclear plants such as Vermont Yankee and Pilgrim in Massachusetts, power plant owners say lower electricity prices, partly due to cheap renewables and partly to stagnant demand, means they can’t be profitable just by selling power.

Programs like the IEP are meant to subsidize such plants – “incentivize” is the industry term – even though some argue there is no need to subsidize nuclear in deregulated markets so they’ll stay open if they are needed.

The IEP approved last week will be applied to the winters of 2023 and 2024, after a different subsidy program expires. It sets prices, despite warnings about rushing pricing changes from industry groups, for stocking certain amounts of fuel and payments during any “trigger” event, defined as a day when the average of high and low temperatures at Bradley International Airport in Connecticut is no more than 17 degrees Fahrenheit.

These payments will be made on top of a complex system of grid auctions used to decide how much various plants get paid for generating electricity at which times.

ISO-NE estimates the new program will cost between $102 million and $148 million each winter, depending on weather and market conditions.

It says the payments are open to plants that burn oil, coal, nuclear fuel, wood chips or trash; utility-scale battery storage facilities; and hydropower dams “that store water in a pond or reservoir.” Natural gas plants can participate if they guarantee to have fuel available, but that seems less likely because of winter heating contracts.

A major complaint and groups that filed petitions opposing the project is that ISO-NE presented little supporting evidence of how prices, amount and overall cost were determined. ISO-NE argued that there wasn’t time for such analysis before the Mystic shutdown, and FERC agreed.

“The proposal is a step in the right direction … while ISO-NE finishes developing a long-term market solution,” the commission said in its ruling.

The program is the latest example of complexities facing the nation’s electricity system evolves in the face of solar and wind power, which produce electricity so cheaply that they can render traditional power uneconomic but which can’t always produce power on demand, prompting discussions of Texas grid improvements among policymakers. Another major factor is climate change, which has increased the pressure to support renewable alternatives to plants that burn fossil fuels, as well as stagnant electricity demand caused by increased efficiency.

Opponents, including many environmental groups, say electricity utilities and regulators are too quick to prop up existing systems, as the 145-mile Maine transmission line debate shows, built when electricity was sent one way from a few big plants to many customers. They argue that to combat climate change as well as limit cost, the emphasis must be on developing “non-wire alternatives” such as smart systems for controlling demand, in order to take advantage of the current system in which electricity goes two ways, such as from rooftop solar back into the grid.

 

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