Oglethorpe Power to build biomass generation

Near-Field Thermophotovoltaics captures radiated energy across a nanoscale gap, using thin-film photovoltaic cells and indium gallium arsenide to boost power density and efficiency, enabling compact Army portable power from emitters via radiative heat transfer.

Key Points

A nanoscale TPV method capturing near-field photons for higher power density at lower emitter temperatures.

✅ Nanoscale gap boosts radiative transfer and usable photon flux

✅ Thin-film InGaAs cells recycle sub-band-gap photons via reflector

✅ Achieved ~5 kW/m2 power density with higher efficiency

With the addition of sensors and enhanced communication tools, providing lightweight, portable power has become even more challenging, with concepts such as power from falling snow illustrating how diverse new energy-harvesting approaches are. Army-funded research demonstrated a new approach to turning thermal energy into electricity that could provide compact and efficient power for Soldiers on future battlefields.

Hot objects radiate light in the form of photons into their surroundings. The emitted photons can be captured by a photovoltaic cell and converted to useful electric energy. This approach to energy conversion is called far-field thermophotovoltaics, or FF-TPVs, and has been under development for many years; however, it suffers from low power density and therefore requires high operating temperatures of the emitter.

The research, conducted at the University of Michigan and published in Nature Communications, demonstrates a new approach, where the separation between the emitter and the photovoltaic cell is reduced to the nanoscale, enabling much greater power output than what is possible with FF-TPVs for the same emitter temperature.

This approach, which enables capture of energy that is otherwise trapped in the near-field of the emitter is called near-field thermophotovoltaics or NF-TPV and uses custom-built photovoltaic cells and emitter designs ideal for near-field operating conditions, alongside emerging smart solar inverters that help manage conversion and delivery.

This technique exhibited a power density almost an order of magnitude higher than that for the best-reported near-field-TPV systems, while also operating at six-times higher efficiency, paving the way for future near-field-TPV applications, including remote microgrid deployments in extreme environments, according to Dr. Edgar Meyhofer, professor of mechanical engineering, University of Michigan.

"The Army uses large amounts of power during deployments and battlefield operations and must be carried by the Soldier or a weight constrained system," said Dr. Mike Waits, U.S. Army Combat Capabilities Development Command's Army Research Laboratory. "If successful, in the future near-field-TPVs could serve as more compact and higher efficiency power sources for Soldiers as these devices can function at lower operating temperatures than conventional TPVs."

The efficiency of a TPV device is characterized by how much of the total energy transfer between the emitter and the photovoltaic cell is used to excite the electron-hole pairs in the photovoltaic cell, where insights from near-light-speed conduction research help contextualize performance limits in semiconductors. While increasing the temperature of the emitter increases the number of photons above the band-gap of the cell, the number of sub band-gap photons that can heat up the photovoltaic cell need to be minimized.

"This was achieved by fabricating thin-film TPV cells with ultra-flat surfaces, and with a metal back reflector," said Dr. Stephen Forrest, professor of electrical and computer engineering, University of Michigan. "The photons above the band-gap of the cell are efficiently absorbed in the micron-thick semiconductor, while those below the band-gap are reflected back to the silicon emitter and recycled."

The team grew thin-film indium gallium arsenide photovoltaic cells on thick semiconductor substrates, and then peeled off the very thin semiconductor active region of the cell and transferred it to a silicon substrate, informing potential interfaces with home battery systems for distributed use.

All these innovations in device design and experimental approach resulted in a novel near-field TPV system that could complement distributed resources in virtual power plants for resilient operations.

"The team has achieved a record ~5 kW/m2 power output, which is an order of magnitude larger than systems previously reported in the literature," said Dr. Pramod Reddy, professor of mechanical engineering, University of Michigan.

Researchers also performed state-of-the-art theoretical calculations to estimate the performance of the photovoltaic cell at each temperature and gap size, informing hybrid designs with backup fuel cell solutions that extend battery life, and showed good agreement between the experiments and computational predictions.

"This current demonstration meets theoretical predictions of radiative heat transfer at the nanoscale, and directly shows the potential for developing future near-field TPV devices for Army applications in power and energy, communication and sensors," said Dr. Pani Varanasi, program manager, DEVCOM ARL that funded this work.

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Ireland 65% Renewable Grid Capability showcases world leading integration of intermittent wind and solar, smart grid flexibility, EU-SysFlex learnings, and the Celtic Interconnector to enhance stability, exports, and energy security across the European grid.

Key Points

Ireland can run its isolated power system with 65% variable wind and solar, informing EU grid integration and scaling.

✅ 65% system non-synchronous penetration on an isolated grid

✅ EU-SysFlex roadmap supports large-scale renewables integration

✅ Celtic Interconnector adds 700MW capacity and stability

Ireland is now able to cope with 65% of its electricity coming from intermittent electricity sources like wind and solar, as highlighted by Ireland's green electricity outlook today – an expertise Energy Minister Denish Naugthen believes can be replicated on a larger scale as Europe moves towards 50% renewable power by 2030.

Denis Naughten is an Irish politician who serves as Minister for Communications, Climate Action and Environment since May 2016.

Naughten spoke to editor Frédéric Simon on the sidelines of a EURACTIV event in the European  Parliament to mark the launch of EU-SysFlex, an EU-funded project, which aims to create a long-term roadmap for the large-scale integration of renewable energy on electricity grids.

What is the reason for your presence in Brussels today and the main message that you came to deliver?

The reason that I’m here today is that we’re going to share the knowledge what we have developed in Ireland, right across Europe. We are now the global leaders in taking variable renewable electricity like wind and solar onto our grid.

We can take a 65% loading on to the grid today – there is no other isolated grid in the world that can do that. We’re going to get up to 75% by 2020. This is a huge technical challenge for any electricity grid and it’s going to be a problem that is going to grow and grow across Europe, even as Europe's electricity demand rises in the coming years, as we move to 50% renewables onto our grid by 2030.

And our knowledge and understanding can be used to help solve the problems right across Europe. And the sharing of technology can mean that we can make our own grid in Ireland far more robust.

What is the contribution of Ireland when it comes to the debate which is currently taking place in Europe about raising the ambition on renewable energy and make the grid fit for that? What are the main milestones that you see looking ahead for Europe and Ireland?

It is a challenge for Europe to do this, but we’ve done it Ireland. We have been able to take a 65% loading of wind power on our grid, with Irish wind generation hitting records recently, so we can replicate that across Europe.

Yes it is about a much larger scale and yes, we need to work collaboratively together, reflecting common goals for electricity networks worldwide – not just in dealing with the technical solutions that we have in Ireland at the fore of this technology, but also replicating them on a larger scale across Europe.

And I believe we can do that, I believe we can use the learnings that we have developed in Ireland and amplify those to deal with far bigger challenges that we have on the European electricity grid.

Trialogue talks have started at European level about the reform of the electricity market. There is talk about decentralised energy generation coming from small-scale producers. Do you see support from all the member states in doing that? And how do you see the challenges ahead on a political level to get everyone on board on such a vision?

I don’t believe there is a political problem here in relation to this. I think there is unanimity across Europe that we need to support consumers in producing electricity for self-consumption and to be able to either store or put that back into the grid.

The issues here are more technical in nature. And how you support a grid to do that. And who actually pays for that. Ireland is very much a microcosm of the pan-European grid and how we can deal with those challenges.

What we’re doing at the moment in Ireland is looking at a pilot scheme to support consumers to generate their own electricity to meet their own needs and to be able to store that on site.

I think in the years to come a lot of that will be actually done with more battery storage in the form of electric vehicles and people would be able to transport that energy from one location to another as and when it’s needed. In the short term, we’re looking at some novel solutions to support consumers producing their own electricity and meeting their own needs.

So I think this is complex from a technical point of view at the moment, I don’t think there is an unwillingness from a political perspective to do it, and I think working with this particular initiative and other initiatives across Europe, we can crack those technical challenges.

To conclude, last year, the European Commission allocated €4 million to a project to link up the Irish electricity grid to France. How is that going to benefit Ireland? And is that related to worries that you may have over Brexit?

The plan, which is called the Celtic Interconnector, is to link France with the Irish electricity grid. It’s going to have a capacity of about 700MW. It allows us to provide additional stability on our grid and enables us to take more renewables onto the grid. It also allows us to export renewable electricity onto the main European grid as well, and provide stability to the French network.

So it’s a benefit to both individual networks as well as allowing far more renewables onto the grid. We’ve been working quite closely with RTE in France and with both regulators. We’re hoping to get the support of the European Commission to move it now from the design stage onto the construction stage. And I understand discussions are ongoing with the Commission at present with regard to that.

And that is going to diversify potential sources of electricity coming in for Ireland in a situation which is pretty uncertain because of Brexit, correct?

Well, I don’t think there is uncertainty because of Brexit in that we have agreements with the United Kingdom, we’re still going to be part of the broader energy family in relation to back-and-forth supply across the Irish Sea, with grid reinforcements in Scotland underscoring reliability needs.  But I think it is important in terms of meeting the 15% interconnectivity that the EU has set in relation to electricity.

And also in relation of providing us with an alternative support in relation to electricity supply outside of Britain. Because Britain is now leaving the European Union and I think this is important from a political point of view, and from a broader energy security point of view. But we don’t see it in the short term as causing threats in relation to security of supply.

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Philippines Nuclear Energy Policy aims to add nuclear power to the energy mix via executive order, meeting rising electricity demand with 24/7 baseload while balancing safety, renewables, and imported fuel dependence in the Philippines.

Key Points

A government plan to include nuclear power in the energy mix to meet demand, ensure baseload, and uphold safety.

✅ Executive order proposed by Energy Secretary Alfonso Cusi

✅ Targets 24/7 baseload, rising electricity demand

✅ Balances safety, renewables, and energy security

Phillipines Presidential spokesman Salvador Panelo said Energy Secretary Alfonso Cusi made the proposal during last Monday's Cabinet meeting in Malacaaang. "Secretary Cusi likewise sought the approval of the issuance of a proposed executive order for the inclusion of nuclear power, including next-gen nuclear options in the country's energy mix as the Philippines is expected to the rapid growth in electricity and electricity demand, in which, 24/7 power is essential and necessary," Panelo said in a statement.

Panelo said Duterte would study the energy chief's proposal, as China's nuclear development underscores regional momentum. In the 1960s until the mid 80s, the late president Ferdinand Marcos adopted a nuclear energy program and built the Bataan Nuclear Plant.

The nuclear plant was mothballed after Corazon Aquino became president in 1986. There have been calls to revive the nuclear plant, saying it would help address the Philippines' energy supply issues. Some groups, however, said such move would be expensive and would endanger the lives of people living near the facility, citing Three Mile Island as a cautionary example.

Panelo said proposals to revive the Bataan Nuclear Plant were not discussed during the Cabinet meeting, even as debates like California's renewable classification continue to shape perceptions. Indigenous energy sources natural gas, hydro, coal, oil, geothermal, wind, solar, biomassand ethanol constitute more than half or 59.6%of the Philippines' energy mix.

Imported oil make up 31.7% while imported coal, reflecting the country's coal dependency, contribute about 8.7%.

Imported ethanol make up 0.1% of the energy mix, even as interest in atomic energy rises globally.

In 2018, Duterte said safety should be the priority when deciding whether to tap nuclear energy for the country's power needs, as countries like India's nuclear restart proceed with their own safeguards.

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Raindrop Triboelectric Energy Harvesting converts falling water into electricity using Teflon (PTFE) on indium tin oxide and an aluminum electrode, forming a transient water bridge; a low frequency nanogenerator for renewable, static electricity harvesting.

Key Points

A method using PTFE, ITO, and an aluminum electrode to turn raindrop impacts into low frequency electrical power.

✅ PTFE on ITO boosts charge transfer efficiency.

✅ Water bridge links electrodes for rapid discharge.

✅ Low frequency output suits continuous energy harvesting.

Scientists at the City University of Hong Kong have used a Teflon-coated surface and a phenomenon called triboelectricity to generate a charge from raindrops. “Here we develop a device to harvest energy from impinging water droplets by using an architecture that comprises a polytetrafluoroethylene [Teflon] film on an indium tin oxide substrate plus an aluminium electrode,” they explain in their new paper in Nature as a step toward cheap, abundant electricity in the long term.

Triboelectricity itself is an old concept. The word means “friction electricity”—from the Greek tribo, to rub or wear down, which is why a diatribe tires you out—and dates back a long, long time. Static electricity is the most famous kind of triboelectric, and related work has shown electricity from the night sky can be harvested as well in niche setups. In most naturally occurring kinds, scientists have studied triboelectric in order to avoid its effects, like explosions inside of grain silos or hospital workers touching off pure oxygen. (Blowing sand causes an electric field, and NASA even worries about static when astronauts eventually land on Mars.)

One of the most studied forms of intentional and useful triboelectric is in systems such as ocean wave generators where the natural friction of waves meets nanogenerators of triboelectric energy. These even already use Teflon, which has natural conductivity that makes it ideal for this job. But triboelectricity is chaotic, and harnessing it generally involves a bunch of complicated, intersecting variables that can vary with the hourly weather. Promises of static electricity charging devices have often been, well, so much hot, sandy wind.

The scientists at City University of Hong Kong used triboelectric ideas to turn falling raindrops into energy. They say previous versions of the same idea were not very efficient, with materials that didn’t allow for high-fidelity transfer of electrical charge. (Many sources of renewable energy aren’t yet as efficient to turn into power, both because of developing technology and because their renewability means even less efficient use could be better than, for example, fossil fuels, and advances in renewable energy storage could help.)

“[A]chieving a high density of electrical power generation is challenging,” the team explains in its paper. “Traditional hydraulic power generation mainly uses electromagnetic generators that are heavy, bulky, and become inefficient with low water supply.” Diversifying how power is generated by water sources such as oceans and rivers is good for the existing infrastructure as well as new installations.

The research team found that as simulated raindrops fell on their device, the way the water accumulated and spread created a link between their two electrodes, one Teflon-coated and the other aluminum. This watery de facto wire link closes the loop and allows accumulated energy to move through the system. Because it’s a mechanical setup, it’s not limited to salty seawater, and because the medium is already water, its potential isn’t affected by ambient humidity either.

Raindrop energy is very low frequency, which means this tech joins many other existing pushes to harvest continuously available, low frequency natural energy, including underwater 'kites' that exploit steady currents. To make an interface that increases “instantaneous power density by several orders of magnitude over equivalent devices,” as the researchers say they’ve done here, could represent a major step toward feasibility in triboelectric generation.

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New York Climate Transition Costs highlight rising utility bills for ratepayers as the state pursues renewable energy, electrification, and a zero-emissions grid, with Inflation Reduction Act funding to offset consumer burdens while delivering health benefits.

Key Points

Ratepayer-funded costs to meet New York's renewable targets and zero-emissions grid, offset by federal incentives.

✅ $48B in projects funded by consumers over two decades

✅ Up to 10% of utility bills already paid by some upstate users

✅ Targets: 70% renewables by 2030; zero-emissions grid by 2040

A generational push to tackle climate change in New York that includes its Green New Deal is quickly becoming a pocketbook issue headed into 2024.

Some upstate New York electric customers are already paying 10 percent of their electricity bills to support the state’s effort to move off fossil fuels and into renewable energy. In the coming years, people across the state can expect to give up even bigger chunks of their income to the programs — $48 billion in projects is set to be funded by consumers over the next two decades.

The scenario is creating a headache for New York Democrats grappling with the practical and political risk of the transition.

It’s an early sign of the dangers Democrats across the country will face as they press forward with similar policies at the state and federal level. New Jersey, Maryland and California are also wrestling with the issue and, in some cases, are reconsidering their ambitious plans, including a 100% carbon-free mandate in California.

“This is bad politics. This is politics that are going to hurt all New Yorkers,” said state Sen. Mario Mattera, a Long Island Republican who has repeatedly questioned the costs of the state’s climate law and who will pay for it.

Democrats, Mattera said, have been unable to explain effectively the costs for the state’s goals. “We need to transition into renewable energy at a certain rate, a certain pace,” he said.

Proponents say the switch will ultimately lower energy bills by harnessing the sun and wind, result in significant health benefits and — critically — help stave off the most devastating climate change scenarios. And they hope new money to go green from the Inflation Reduction Act, celebrating its one-year anniversary, can limit costs to consumers.

New York has statutory mandates calling for 70 percent renewable electricity by 2030 and a fully “zero emissions” grid by 2040, among the most aggressive targets in the country, aligning with a broader path to net-zero electricity by mid-century. The grid needs to be greened, while demand for electricity is expected to more than double by 2050 — the same year when state law requires emissions to be cut by 85 percent from 1990 levels.

But some lawmakers in New York, particularly upstate Democrats, and similar moderates across the nation are worried about moving too quickly and sparking a backlash against higher costs, as debates over Minnesota's 2050 carbon-free plan illustrate. The issue is another threat to Democrats heading into the critical 2024 battleground House races in New York, which will be instrumental in determining control of Congress.

Even Gov. Kathy Hochul, a Democrat who is fond of saying that “we’re the last generation to be able to do anything” about climate change, last spring balked at the potential price tag of a policy to achieve New York’s climate targets, a concern echoed in debates over a fully renewable grid by 2030 elsewhere. And she’s not the only top member of her party to say so.

“If it’s all just going to be passed along to the ratepayers — at some point, there’s a breaking point, and we don’t want to lose public support for this agenda,” state Comptroller Tom DiNapoli, a Democrat, warned in an interview.

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Sustainable Marine tidal energy delivers in-stream power to Nova Scotia's grid from Grand Passage, proving low-impact, renewable generation and advancing a floating tidal array at FORCE and Minas Passage in the Bay of Fundy.

Key Points

The first in-stream tidal project supplying clean power to Nova Scotia's grid, proven at Grand Passage.

✅ First to deliver in-stream tidal power to Canada's grid

✅ Demonstration at Grand Passage informs FORCE deployments

✅ Low-impact design and environmental monitoring validated

Sustainable Marine has officially powered up its tidal energy operation in Canada and is delivering clean electricity to the power system in Nova Scotia, on the country’s Atlantic coast, as the province moves to increase wind and solar projects in the years ahead. The company’s system in Grand Passage is the first to deliver in-stream tidal power to the grid in Canada, following provincial approval to harness Bay of Fundy tides that is spurring further development.

The system start-up is the culmination of more than a decade of research, development and testing, including lessons from Scottish tidal projects in recent years and a powerful tidal turbine feeding onshore grids, managing the technical challenges associated with operating in highly energetic environments and proving the ultra-low environmental impact of the tidal technology.

Sustainable Marine is striving to deliver the world’s first floating tidal array at FORCE (Fundy Ocean Research Centre for Energy). This project will be delivered in phases, drawing upon the knowledge gained and lessons learned in Grand Passage, and insights from offshore wind pilots like France’s first offshore wind turbine in Europe. In the coming months the company will continue to operate the platform at its demonstration site at Grand Passage, gradually building up power production, while New York and New England clean energy demand continues to rise, to further prove the technology and environmental monitoring systems, before commencing deployments in the Minas Passage – renowned as the Everest of tidal energy.

The Bay of Fundy’s huge tidal energy resource contains more than four times the combined flow of every freshwater river in the world, with the potential to generate approximately 2,500 MW of green energy, underscoring why independent electricity planning will be important for integrating marine renewables.

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