Built-in solar struggles with cost, efficiency

By Reuters


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The market for solar modules that are designed to be integrated into buildings in the form of shingles or windows faces a tough challenge given their higher costs and lower efficiency than competing products.

Building-integrated photovoltaics, or BIPVs, made by companies such as Energy Conversion Devices and Ascent Solar, are designed to be an integral part of buildings, in contrast to the photovoltaic panels made by First Solar, Suntech and others that need to be retrofitted on roofs.

Given their unobtrusive nature, BIPVs were once touted as the next big thing in solar power, but have so far not taken off as expected.

After a promising initial run, BIPV makers ran into the global financial crisis that brought construction activity — to which most BIPV sales are typically tied — to a near halt.

The immediate future doesn't look much brighter.

"It is going to be hard to see a lot of growth, given the economic challenges facing a lot of the traditional purchases of BIPVs," Simmons & Co analyst Burt Chao said.

"BIPV companies could languish for some time," he said. "Given the outlook for solar in 2011, with the subsidy reductions, companies are going to find it challenging."

Europe's largest solar markets — Germany, Italy, Spain and the Czech Republic — have unveiled plans to cut subsidies for the solar sector, which some said has been oversubsidized, to preserve cash amid Europe's debt crisis.

The steep drop in construction levels has dealt a major blow to BIPV makers. Energy Conversion Devices, for instance, slumped back into the red, following five consecutive quarters of estimate-topping results.

It was forced to cut jobs and scale down capacity utilization to as low as 25 percent as demand fell.

"ECD's original strategy was to partner with roofing and building material companies," Wedbush analyst Christine Hersey said. "Then the construction market fell apart and they had to switch gears."

Last year, when Dow Chemical unveiled plans to roll out a new rooftop shingle — likely to be widely available next year — it also said it would partner with home builders Lennar Corp and PulteGroup Inc in North America.

But construction activity has yet to pick up significantly. New U.S. home construction hit its lowest level in eight months in June, signaling the economy lost momentum in the second quarter.

BIPV systems are limited mostly to roofing tiles, which operate at lower efficiencies than solar panels and have been too expensive to gain wide acceptance.

Dow Chemical said its new rooftop shingles will use thin-film cells that will cost 10 to 15 percent less on a per-watt basis than rival polysilicon cells, but will still operate at a lower efficiency than some solar cells.

And with cost leader First Solar bringing panel manufacturing costs down to 76 cents per watt and reporting conversion efficiency — the proportion of sunlight received that is converted to electricity — of 11.2 percent in the latest second quarter, BIPV makers have their work cut out.

For instance, Energy Conversion reported a conversion efficiency of only 8.2 percent and manufacturing costs as high as $2.95 per watt in the quarter ended March 31.

While the company hopes to bring costs down to 95 cents per watt, when it operates at full capacity, and raise conversion efficiency to 12 percent by 2012, this still might not be enough to give it an edge over some of its rivals.

Lower conversion efficiency typically means more panels are needed to generate a given amount of electricity.

"This is a problem when you are looking at how much power you can get out of a rooftop, where space is limited," Wedbush's Hersey said.

As the industry struggles to compete effectively with photovoltaic panels, analysts say growth will be difficult in the near term, but could be possible in another year and a half.

"If BIPV players can get their costs down — they have to — once you get past 2011, you might see some growth in that space," Simmons' Chao said.

"Right now, they have to be very cautious."

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How the 787 uses electricity to maximise efficiency

Boeing 787 More-Electric Architecture replaces pneumatics with bleedless pressurization, VFSG starter-generators, electric brakes, and heated wing anti-ice, leveraging APU, RAT, batteries, and airport ground power for efficient, redundant electrical power distribution.

 

Key Points

An integrated, bleedless electrical system powering start, pressurization, brakes, and anti-ice via VFSGs, APU and RAT.

✅ VFSGs start engines, then generate 235Vac variable-frequency power

✅ Bleedless pressurization, electric anti-ice improve fuel efficiency

✅ Electric brakes cut hydraulic weight and simplify maintenance

 

The 787 Dreamliner is different to most commercial aircraft flying the skies today. On the surface it may seem pretty similar to the likes of the 777 and A350, but get under the skin and it’s a whole different aircraft.

When Boeing designed the 787, in order to make it as fuel efficient as possible, it had to completely shake up the way some of the normal aircraft systems operated. Traditionally, systems such as the pressurization, engine start and wing anti-ice were powered by pneumatics. The wheel brakes were powered by the hydraulics. These essential systems required a lot of physical architecture and with that comes weight and maintenance. This got engineers thinking.

What if the brakes didn’t need the hydraulics? What if the engines could be started without the pneumatic system? What if the pressurisation system didn’t need bleed air from the engines? Imagine if all these systems could be powered electrically… so that’s what they did.

 

Power sources

The 787 uses a lot of electricity. Therefore, to keep up with the demand, it has a number of sources of power, much as grid operators track supply on the GB energy dashboard to balance loads. Depending on whether the aircraft is on the ground with its engines off or in the air with both engines running, different combinations of the power sources are used.

 

Engine starter/generators

The main source of power comes from four 235Vac variable frequency engine starter/generators (VFSGs). There are two of these in each engine. These function as electrically powered starter motors for the engine start, and once the engine is running, then act as engine driven generators.

The generators in the left engine are designated as L1 and L2, the two in the right engine are R1 and R2. They are connected to their respective engine gearbox to generate electrical power directly proportional to the engine speed. With the engines running, the generators provide electrical power to all the aircraft systems.

 

APU starter/generators

In the tail of most commercial aircraft sits a small engine, the Auxiliary Power Unit (APU). While this does not provide any power for aircraft propulsion, it does provide electrics for when the engines are not running.

The APU of the 787 has the same generators as each of the engines — two 235Vac VFSGs, designated L and R. They act as starter motors to get the APU going and once running, then act as generators. The power generated is once again directly proportional to the APU speed.

The APU not only provides power to the aircraft on the ground when the engines are switched off, but it can also provide power in flight should there be a problem with one of the engine generators.

 

Battery power

The aircraft has one main battery and one APU battery. The latter is quite basic, providing power to start the APU and for some of the external aircraft lighting.

The main battery is there to power the aircraft up when everything has been switched off and also in cases of extreme electrical failure in flight, and in the grid context, alternatives such as gravity power storage are being explored for long-duration resilience. It provides power to start the APU, acts as a back-up for the brakes and also feeds the captain’s flight instruments until the Ram Air Turbine deploys.

 

Ram air turbine (RAT) generator

When you need this, you’re really not having a great day. The RAT is a small propeller which automatically drops out of the underside of the aircraft in the event of a double engine failure (or when all three hydraulics system pressures are low). It can also be deployed manually by pressing a switch in the flight deck.

Once deployed into the airflow, the RAT spins up and turns the RAT generator. This provides enough electrical power to operate the captain’s flight instruments and other essentials items for communication, navigation and flight controls.

 

External power

Using the APU on the ground for electrics is fine, but they do tend to be quite noisy. Not great for airports wishing to keep their noise footprint down. To enable aircraft to be powered without the APU, most big airports will have a ground power system drawing from national grids, including output from facilities such as Barakah Unit 1 as part of the mix. Large cables from the airport power supply connect 115Vac to the aircraft and allow pilots to shut down the APU. This not only keeps the noise down but also saves on the fuel which the APU would use.

The 787 has three external power inputs — two at the front and one at the rear. The forward system is used to power systems required for ground operations such as lighting, cargo door operation and some cabin systems. If only one forward power source is connected, only very limited functions will be available.

The aft external power is only used when the ground power is required for engine start.

 

Circuit breakers

Most flight decks you visit will have the back wall covered in circuit breakers — CBs. If there is a problem with a system, the circuit breaker may “pop” to preserve the aircraft electrical system. If a particular system is not working, part of the engineers procedure may require them to pull and “collar” a CB — placing a small ring around the CB to stop it from being pushed back in. However, on the 787 there are no physical circuit breakers. You’ve guessed it, they’re electric.

Within the Multi Function Display screen is the Circuit Breaker Indication and Control (CBIC). From here, engineers and pilots are able to access all the “CBs” which would normally be on the back wall of the flight deck. If an operational procedure requires it, engineers are able to electrically pull and collar a CB giving the same result as a conventional CB.

Not only does this mean that the there are no physical CBs which may need replacing, it also creates space behind the flight deck which can be utilised for the galley area and cabin.


 

 

A normal flight

While it’s useful to have all these systems, they are never all used at the same time, and, as the power sector’s COVID-19 mitigation strategies showed, resilience planning matters across operations. Depending on the stage of the flight, different power sources will be used, sometimes in conjunction with others, to supply the required power.

 

On the ground

When we arrive at the aircraft, more often than not the aircraft is plugged into the external power with the APU off. Electricity is the blood of the 787 and it doesn’t like to be without a good supply constantly pumping through its system, and, as seen in NYC electric rhythms during COVID-19, demand patterns can shift quickly. Ground staff will connect two forward external power sources, as this enables us to operate the maximum number of systems as we prepare the aircraft for departure.

Whilst connected to the external source, there is not enough power to run the air conditioning system. As a result, whilst the APU is off, air conditioning is provided by Preconditioned Air (PCA) units on the ground. These connect to the aircraft by a pipe and pump cool air into the cabin to keep the temperature at a comfortable level.

 

APU start

As we near departure time, we need to start making some changes to the configuration of the electrical system. Before we can push back , the external power needs to be disconnected — the airports don’t take too kindly to us taking their cables with us — and since that supply ultimately comes from the grid, projects like the Bruce Power upgrade increase available capacity during peaks, but we need to generate our own power before we start the engines so to do this, we use the APU.

The APU, like any engine, takes a little time to start up, around 90 seconds or so. If you remember from before, the external power only supplies 115Vac whereas the two VFSGs in the APU each provide 235Vac. As a result, as soon as the APU is running, it automatically takes over the running of the electrical systems. The ground staff are then clear to disconnect the ground power.

If you read my article on how the 787 is pressurised, you’ll know that it’s powered by the electrical system. As soon as the APU is supplying the electricity, there is enough power to run the aircraft air conditioning. The PCA can then be removed.


 

 

Engine start

Once all doors and hatches are closed, external cables and pipes have been removed and the APU is running, we’re ready to push back from the gate and start our engines. Both engines are normally started at the same time, unless the outside air temperature is  below 5°C.

On other aircraft types, the engines require high pressure air from the APU to turn the starter in the engine. This requires a lot of power from the APU and is also quite noisy. On the 787, the engine start is entirely electrical.

Power is drawn from the APU and feeds the VFSGs in the engines. If you remember from earlier, these fist act as starter motors. The starter motor starts the turn the turbines in the middle of the engine. These in turn start to turn the forward stages of the engine. Once there is enough airflow through the engine, and the fuel is igniting, there is enough energy to continue running itself.


 

 

After start

Once the engine is running, the VFSGs stop acting as starter motors and revert to acting as generators. As these generators are the preferred power source, they automatically take over the running of the electrical systems from the APU, which can then be switched off. The aircraft is now in the desired configuration for flight, with the 4 VFSGs in both engines providing all the power the aircraft needs.

As the aircraft moves away towards the runway, another electrically powered system is used — the brakes. On other aircraft types, the brakes are powered by the hydraulics system. This requires extra pipe work and the associated weight that goes with that. Hydraulically powered brake units can also be time consuming to replace.

By having electric brakes, the 787 is able to reduce the weight of the hydraulics system and it also makes it easier to change brake units. “Plug in and play” brakes are far quicker to change, keeping maintenance costs down and reducing flight delays.

 

In-flight

Another system which is powered electrically on the 787 is the anti-ice system. As aircraft fly though clouds in cold temperatures, ice can build up along the leading edge of the wing. As this reduces the efficiency of the the wing, we need to get rid of this.

Other aircraft types use hot air from the engines to melt it. On the 787, we have electrically powered pads along the leading edge which heat up to melt the ice.

Not only does this keep more power in the engines, but it also reduces the drag created as the hot air leaves the structure of the wing. A double win for fuel savings.

Once on the ground at the destination, it’s time to start thinking about the electrical configuration again. As we make our way to the gate, we start the APU in preparation for the engine shut down. However, because the engine generators have a high priority than the APU generators, the APU does not automatically take over. Instead, an indication on the EICAS shows APU RUNNING, to inform us that the APU is ready to take the electrical load.


 

 

Shutdown

With the park brake set, it’s time to shut the engines down. A final check that the APU is indeed running is made before moving the engine control switches to shut off. Plunging the cabin into darkness isn’t a smooth move. As the engines are shut down, the APU automatically takes over the power supply for the aircraft. Once the ground staff have connected the external power, we then have the option to also shut down the APU.

However, before doing this, we consider the cabin environment. If there is no PCA available and it’s hot outside, without the APU the cabin temperature will rise pretty quickly. In situations like this we’ll wait until all the passengers are off the aircraft until we shut down the APU.

Once on external power, the full flight cycle is complete. The aircraft can now be cleaned and catered, ready for the next crew to take over.

 

Bottom line

Electricity is a fundamental part of operating the 787. Even when there are no passengers on board, some power is required to keep the systems running, ready for the arrival of the next crew. As we prepare the aircraft for departure and start the engines, various methods of powering the aircraft are used.

The aircraft has six electrical generators, of which only four are used in normal flights. Should one fail, there are back-ups available. Should these back-ups fail, there are back-ups for the back-ups in the form of the battery. Should this back-up fail, there is yet another layer of contingency in the form of the RAT. A highly unlikely event.

The 787 was built around improving efficiency and lowering carbon emissions whilst ensuring unrivalled levels safety, and, in the wider energy landscape, perspectives like nuclear beyond electricity highlight complementary paths to decarbonization — a mission it’s able to achieve on hundreds of flights every single day.

 

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Tunisia invests in major wind farm as part of longterm renewable energy plan

Sidi Mansour Wind Farm Tunisia will deliver 30 MW as an IPP, backed by UPC Renewables and CFM, under a STEG PPA, supporting 2030 renewable energy targets, grid connection, job creation, and CO2 emissions reduction.

 

Key Points

A 30 MW wind IPP by UPC and CFM in Sidi Mansour, supplying STEG and advancing Tunisia's 2030 renewable target.

✅ 30 MW capacity under STEG PPA, first wind IPP in Tunisia

✅ Co-developed by UPC Renewables and Climate Fund Managers

✅ Cuts CO2 by up to 56,645 t and creates about 100 jobs

 

UPC Renewables (UPC) and the Climate Fund Managers (CFM) have partnered to develop a 30 megawatt wind farm in Sidi Mansour, Tunisia, which, amid regional wind expansion efforts, will help the country meet its 30% renewable energy target by 2030.

Tunisia announced the launch of its solar energy plan in 2016, with projects like the 10 MW Tunisian solar park aiming to increase the role of renewables in its electricity generation mix ten-fold to 30%,

This Sidi Mansour Project will help Tunisia meet its goals, reducing its reliance on imported fossil fuels and, mirroring 90 MW Spanish wind build milestones, demonstrating to the world that it is serious about further development of renewable energy investment.

“Chams Enfidha”, the first solar energy station in Tunisia with a capacity of 1 megawatt and located in the Enfidha region. (Ministry of Energy, Mines and Energy Transition Facebook page)

This project will also be among the country’s first Independent Power Producers (IPP). CFM is acting as sponsor, financial adviser and co-developer on the project, in a landscape shaped by IRENA-ADFD funding in developing countries, while UPC will lead the development with its local team. The team will be in charge of permitting, grid connection, land securitisation, assessment of wind resources, contract procurement and engineering.

UPC was selected under the “Authorisation Scheme” tender for the project in 2016, similar to utility-scale developments like a 450 MW U.S. wind farm, and promptly signed a power purchase agreement with Société Tunisienne Electricité et du Gaz (STEG).

Brian Caffyn, chairman of UPC Group, said: “We can start the construction of the Sidi Mansour wind farm in 2020, helping stimulate the Tunisian economy, create local jobs and a social plan for local communities while respecting international environmental protection guidelines.”

Sebastian Surie, CFM’s regional head of Africa, added: “CFM is thrilled to partner with a leading wind developer in the Sidi Mansour Wind Project to assist Tunisia in meeting its renewable energy goals. As potentially the first Wind IPP in Tunisia, this Project will be a testament to how CI1’s full life-cycle financing solution can unlock investment in renewable energy in new markets, as seen in an Irish offshore wind project globally.”

The project will not only provide electricity, but also reduce CO2 emissions by up to 56,645 tonnes and create some 100 new jobs.

Wind turbine in El Haouaria, Tunisia, highlighting advances such as a huge offshore wind turbine that can power 18,000 homes. (Reuters)

Tunisia’s first power station, “Chams Enfidha,” inaugurated at the beginning of July, has a capacity of one megawatt, with an estimated cost of 3.3 million dinars ($1.18 million). The state invested 2.3 million dinars into the project ($820,000), with the remaining 1 million dinars ($360,000) provided by a private investor.

 

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Canada Makes Historic Investments in Tidal Energy in Nova Scotia

Canada Tidal Energy Investment drives Nova Scotia's PLAT-I floating tidal array at FORCE, advancing renewable energy, clean electricity, emissions reductions, and green jobs while delivering 9 MW of predictable ocean power to the provincial grid.

 

Key Points

Federal funding for a floating tidal array delivering 9 MW of clean power in Nova Scotia, cutting annual CO2 emissions.

✅ $28.5M for Sustainable Marine's PLAT-I floating array

✅ Delivers 9 MW to Nova Scotia's grid via FORCE

✅ Cuts 17,000 tonnes CO2 yearly and creates local jobs

 

Canada has an abundance of renewable energy sources that are helping power our country's clean growth future and the Government of Canada is investing in renewable energy and grid modernization to reduce emissions, create jobs and invigorate local economies in a post COVID-19 pandemic world.

The Honourable Seamus O'Regan, Canada's Minister of Natural Resources, today announced one of Canada's largest-ever investments in tidal energy development — $28.5 million to Sustainable Marine in Nova Scotia to deliver Canada's first floating tidal energy array.

Sustainable Marine developed an innovative floating tidal energy platform called PLAT-I as part of advances in ocean and river power technologies that has undergone rigorous testing on the waters of Grand Passage for nearly two years. A second platform is currently being assembled in Meteghan, Nova Scotia and will be launched in Grand Passage later this year for testing before relocation to the Fundy Ocean Research Centre for Energy (FORCE) in 2021. These platforms will make up the tidal energy array.  

The objective of the project is to provide up to nine megawatts of predictable and clean renewable electricity to Nova Scotia's electrical grid infrastructure. This will reduce greenhouse gas emissions by 17,000 tonnes of carbon dioxide a year while creating new jobs in the province. The project will also demonstrate the ability to harness tides as a reliable source of renewable electricity to power homes, vehicles and businesses.

Tidal energy — a clean, renewable energy source generated by ocean tides and currents, alongside evolving offshore wind regulations that support marine renewables — has the potential to significantly reduce Canada's greenhouse gas emissions and improve local air quality by displacing electricity generated from fossil fuels.

Minister O'Regan made the announcement at the Marine Renewables Canada 2020 Fall Forum, which brings together its members and industry to identify opportunities and strategize a path forward for marine renewable energy sources.

Funding for the project comes from Natural Resources Canada's Emerging Renewables Power Program, part of Canada's more than $180-billion Investing in Canada infrastructure plan for public transit projects, green infrastructure, social infrastructure, trade and transportation routes and Canada's rural and northern communities, as Prairie provinces' renewable growth accelerates nationwide.

 

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New England Is Burning the Most Oil for Electricity Since 2018

New England oil-fired generation surges as ISO New England manages a cold snap, dual-fuel switching, and a natural gas price spike, highlighting winter reliability challenges, LNG and pipeline limits, and rising CO2 emissions.

 

Key Points

Reliance on oil-burning power plants during winter demand spikes when natural gas is costly or constrained.

✅ Driven by dual-fuel switching amid high natural gas prices

✅ ISO-NE winter reliability rules encourage oil stockpiles

✅ Raises CO2 emissions despite coal retirements and renewables growth

 

New England is relying on oil-fired generators for the most electricity since 2018 as a frigid blast boosts demand for power and natural gas prices soar across markets. 

Oil generators were producing more than 4,200 megawatts early Thursday, accounting for about a quarter of the grid’s power supply, according to ISO New England. That was the most since Jan. 6, 2018, when oil plants produced as much as 6.4 gigawatts, or 32% of the grid’s output, said Wood Mackenzie analyst Margaret Cashman.  

Oil is typically used only when demand spikes, because of higher costs and emissions concerns. Consumption has been consistently high over the past three weeks as some generators switch from gas, which has surged in price in recent months. New England generators are producing power from oil at an average rate of almost 1.8 gigawatts so far this month, the highest for January in at least five years. 

Oil’s share declined to 16% Friday morning ahead of an expected snowstorm, which was “a surprise,” Cashman said. 

“It makes me wonder if some of those generators are aiming to reserve their fuel for this weekend,” she said.

During the recent cold snap, more than a tenth of the electricity generated in New England has been produced by power plants that haven’t happened for at least 15 years.

Burning oil for electricity was standard practice throughout the region for decades. It was once our most common fuel for power and as recently as 2000, fully 19% of the six-state region’s electricity came from burning oil, according to ISO-New England, more than any other source except nuclear power at the time.

Since then, however, natural gas has gotten so cheap that most oil-fired plants have been shut or converted to burn gas, to the point that just 1% of New England’s electricity came from oil in 2018, whereas about half our power came from natural gas generation regionally during that period. This is good because natural gas produces less pollution, both particulates and greenhouse gasses, although exactly how much less is a matter of debate.

But as you probably know, there’s a problem: Natural gas is also used for heating, which gets first dibs. Prolonged cold snaps require so much gas to keep us warm, a challenge echoed in Ontario’s electricity system as supply tightens, that there might not be enough for power plants – at least, not at prices they’re willing to pay.

After we came close to rolling brownouts during the polar vortex in the 2017-18 winter because gas-fired power plants cut back so much, ISO-NE, which has oversight of the power grid, established “winter reliability” rules. The most important change was to pay power plants to become dual-fuel, meaning they can switch quickly between natural gas and oil, and to stockpile oil for winter cold snaps.

We’re seeing that practice in action right now, as many dual-fuel plants have switched away from gas to oil, just as was intended.

That switch is part of the reason EPA says the region’s carbon emissions have gone up in the pandemic, from 22 million tons of CO2 in 2019 to 24 million tons in 2021. That reverses a long trend caused partly by closing of coal plants and partly by growing solar and offshore wind capacity: New England power generation produced 36 million tons of CO2 a decade ago.

So if we admit that a return to oil burning is bad, and it is, what can we do in future winters? There are many possibilities, including tapping more clean imports such as Canadian hydropower to diversify supply.

The most obvious solution is to import more natural gas, especially from fracked fields in New York state and Pennsylvania. But efforts to build pipelines to do that have been shot down a couple of times and seem unlikely to go forward and importing more gas via ocean tanker in the form of liquefied natural gas (LNG) is also an option, but hits limits in terms of port facilities.

Aside from NIMBY concerns, the problem with building pipelines or ports to import more gas is that pipelines and ports are very expensive. Once they’re built they create a financial incentive to keep using natural gas for decades to justify the expense, similar to moves such as Ontario’s new gas plants that lock in generation. That makes it much harder for New England to decarbonize and potentially leaves ratepayers on the hook for a boatload of stranded costs.

 

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A new material made from carbon nanotubes can generate electricity by scavenging energy from its environment

Carbon Nanotube Solvent Electricity enables wire-free electrochemistry as organic solvents like acetonitrile pull electrons, powering alcohol oxidation and packed bed reactors, energy harvesting, and micro- and nanoscale robots via redox-driven current.

 

Key Points

Solvent-driven electron extraction from carbon nanotube particles generates current for electrochemistry.

✅ 0.7 V per particle via solvent-induced electron flow

✅ Packed bed reactors drive alcohol oxidation without wires

✅ Scalable for micro- and nanoscale robots; energy harvesting

 

MIT engineers have discovered a new way of generating electricity, alongside advances in renewable power at night that broaden what's possible, using tiny carbon particles that can create a current simply by interacting with liquid surrounding them.

The liquid, an organic solvent, draws electrons out of the particles, generating a current, unlike devices based on a cheap thermoelectric material that rely on heat, that could be used to drive chemical reactions or to power micro- or nanoscale robots, the researchers say.

"This mechanism is new, and this way of generating energy is completely new," says Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT. "This technology is intriguing because all you have to do is flow a solvent through a bed of these particles. This allows you to do electrochemistry, but with no wires."

In a new study describing this phenomenon, the researchers showed that they could use this electric current to drive a reaction known as alcohol oxidation—an organic chemical reaction that is important in the chemical industry.

Strano is the senior author of the paper, which appears today in Nature Communications. The lead authors of the study are MIT graduate student Albert Tianxiang Liu and former MIT researcher Yuichiro Kunai. Other authors include former graduate student Anton Cottrill, postdocs Amir Kaplan and Hyunah Kim, graduate student Ge Zhang, and recent MIT graduates Rafid Mollah and Yannick Eatmon.

Unique properties
The new discovery grew out of Strano's research on carbon nanotubes—hollow tubes made of a lattice of carbon atoms, which have unique electrical properties. In 2010, Strano demonstrated, for the first time, that carbon nanotubes can generate "thermopower waves." When a carbon nanotube is coated with layer of fuel, moving pulses of heat, or thermopower waves, travel along the tube, creating an electrical current that exemplifies turning thermal energy into electricity in nanoscale systems.

That work led Strano and his students to uncover a related feature of carbon nanotubes. They found that when part of a nanotube is coated with a Teflon-like polymer, it creates an asymmetry, distinct from conventional thermoelectric materials approaches, that makes it possible for electrons to flow from the coated to the uncoated part of the tube, generating an electrical current. Those electrons can be drawn out by submerging the particles in a solvent that is hungry for electrons.

To harness this special capability, the researchers created electricity-generating particles by grinding up carbon nanotubes and forming them into a sheet of paper-like material. One side of each sheet was coated with a Teflon-like polymer, and the researchers then cut out small particles, which can be any shape or size. For this study, they made particles that were 250 microns by 250 microns.

When these particles are submerged in an organic solvent such as acetonitrile, the solvent adheres to the uncoated surface of the particles and begins pulling electrons out of them.

"The solvent takes electrons away, and the system tries to equilibrate by moving electrons," Strano says. "There's no sophisticated battery chemistry inside. It's just a particle and you put it into solvent and it starts generating an electric field."

Particle power
The current version of the particles can generate about 0.7 volts of electricity per particle. In this study, the researchers also showed that they can form arrays of hundreds of particles in a small test tube. This "packed bed" reactor, unlike thin-film waste-heat harvesters for electronics, generates enough energy to power a chemical reaction called an alcohol oxidation, in which an alcohol is converted to an aldehyde or a ketone. Usually, this reaction is not performed using electrochemistry because it would require too much external current.

"Because the packed bed reactor is compact, it has more flexibility in terms of applications than a large electrochemical reactor," Zhang says. "The particles can be made very small, and they don't require any external wires in order to drive the electrochemical reaction."

In future work, Strano hopes to use this kind of energy generation to build polymers using only carbon dioxide as a starting material. In a related project, he has already created polymers that can regenerate themselves using carbon dioxide as a building material, in a process powered by solar energy and informed by devices that generate electricity at night as a complement. This work is inspired by carbon fixation, the set of chemical reactions that plants use to build sugars from carbon dioxide, using energy from the sun.

In the longer term, this approach could also be used to power micro- or nanoscale robots. Strano's lab has already begun building robots at that scale, which could one day be used as diagnostic or environmental sensors. The idea of being able to scavenge energy from the environment, including approaches that produce electricity 'out of thin air' in ambient conditions, to power these kinds of robots is appealing, he says.

"It means you don't have to put the energy storage on board," he says. "What we like about this mechanism is that you can take the energy, at least in part, from the environment."

 

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Almost 500-mile-long lightning bolt crossed three US states

Longest Lightning Flash Record confirmed by WMO: a 477.2-mile megaflash spanning Mississippi, Louisiana, and Texas, detected by satellite sensors, highlighting Great Plains supercell storms, lightning safety, and extreme weather monitoring advancements.

 

Key Points

It is the WMO-verified 477.2-mile megaflash across MS, LA, and TX, detected via satellites.

✅ Spanned 477.2 miles across Mississippi, Louisiana, and Texas

✅ Verified by WMO using space-based lightning detection

✅ Occurs in megaflash-prone regions like the U.S. Great Plains

 

An almost 500-mile long bolt of lightning that lit up the sky across three US states has set a new world record for longest flash, scientists have confirmed.

The lightning bolt, extended a total of 477.2 miles (768 km) and spread across Mississippi, Louisiana, and Texas.

The previous record was 440.6 miles (709 km) and recorded in Brazil in 2018.

Lightning rarely extends over 10 miles and usually lasts under a second, yet utilities plan for severe weather when building long-distance lines such as the TransWest Express transmission project to enhance reliability.

Another lightning flash recorded in 2020 - in Uruguay and Argentina - has also set a new record for duration at 17.1 seconds. The previous record was 16.7 seconds.

"These are extraordinary records from lightning flash events," Professor Randall Cerveny, the WMO's rapporteur of weather and climate extremes, said.

According to the WMO, both records took place in areas prone to intense storms that produce 'megaflashes', namely the Great Plains region of the United States and the La Plata basin of South America's southern cone, where utilities adapting to climate change is an increasing priority.

Professor Cerveny added that greater extremes are likely to exist and are likely to be recorded in the future thanks to advances in space-based lightning detection technology.

The WMO warned that lightning was a hazard and urged people in both regions and around the world to take caution during storms, which can lead to extensive disruptions like the Tennessee power outages reported after severe weather.

"These extremely large and long-duration lightning events were not isolated but happened during active thunderstorms," lightning specialist Ron Holle said in a WMO statement.

"Any time there is thunder heard, it is time to reach a lightning-safe place".

Previously accepted WMO 'lightning extremes' include a 1975 incident in which 21 people were killed by a single flash of a lightning as they huddled inside a tent in Zimbabwe, and modern events show how dangerous weather can also cut electricity for days, as with the Hong Kong typhoon outages that affected families.

In another incident, 469 people were killed when lightning struck the Egyptian town of Dronka in 1994, causing burning oil to flood the town, and major incidents can also disrupt infrastructure, as seen during the LA power outage following a substation fire.

The WMO notes that the only lightning-safe locations are "substantial" buildings with wiring and plumbing, and dedicated lightning protection training helps reinforce these guidelines, rather than structures such as bus stops or those found at beaches.

Fully enclosed metal-topped vehicles are also considered reliably safe, and regional storm safety tips offer additional guidance.

 

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