Doctors urge action on isotope production

By Toronto Star


Substation Relay Protection Training

Our customized live online or in‑person group training can be delivered to your staff at your location.

  • Live Online
  • 12 hours Instructor-led
  • Group Training Available
Regular Price:
$699
Coupon Price:
$599
Reserve Your Seat Today
The federal government must take action to safeguard the supply of medical isotopes after last year's shutdown of a Chalk River reactor left Canada's medical community "teetering on the brink of disaster," a new report says.

Senior nuclear doctors – convened to advise the government during last year's crisis – are urging Ottawa to look at replacing the aging nuclear reactor in Chalk River that now supplies 50 per cent of the world's supply of isotopes.

Finding a replacement reactor has become even more urgent now that Atomic Energy of Canada Ltd. (AECL) decided in May to scrap work on the Maple reactors that were designed to replace the Chalk River facility.

"The Maples were the answer and I'm quite disappointed that the government has made the decision," said Dr. Douglas Abrams, one of the authors of the report who works at the University of Alberta's Cross Cancer Institute.

"That really would have secured the radio-isotope supply for the world," he said.

In a recent report, the doctors write how they were in the dark when the Chalk River nuclear reactor halted production of medical isotopes late last year, a critical oversight that put patients at risk.

Doctors say they were forced to delay diagnostic and treatment procedures for patients across the country when the supply of isotopes dried up last December.

And not knowing how long the isotope shortage would last, they were forced to decide whether to proceed with other procedures for their patients that carried more risk or would be less accurate.

"For patients with serious and often life-threatening conditions, the lack of certainty was chilling," says the report, prepared by health experts called to advise Health Canada after the crisis set in.

"People scheduled for diagnostic tests received little or no information about how long they would have to wait or whether they would have the prescribed test at all," the report said.

The crisis created "emotional stress and tension" at every level of the health-care system as the shortage "compromised" emergency services in some regions and forced some nuclear medicine departments to close completely, it said.

"For the longest time, it was a moving target and that makes it very difficult to figure out what to do.... We didn't know how long it was going to last," Abrams said in an interview.

The Chalk River facility was shut down by Atomic Energy of Canada Ltd. on Nov. 18 for routine maintenance. But the shutdown was unexpectedly prolonged after an inspection found that mandatory safety upgrades ordered by the Canadian Nuclear Safety Commission had not been done.

A separate report blamed the shutdown on poor communications and unclear licence conditions. The "lessons learned" report by Talisman International, an independent consultant, says the AECL licences "were not clear" and did not specify in detail which safety upgrades were to be done.

The report was requested by both the AECL and the safety commission. In a joint statement, they pledged to clarify licence requirements and improve implementation of licensing demands.

The doctors added their own complaints about poor communications, saying they were kept in the dark about the shutdown, making it impossible for them to plan a response to the crisis.

"The nature and full extent of the crisis was simply not known. The nuclear medicine community found itself working on a day-by-day basis, guided by information gleaned from the newspapers," the report said.

"The ability to provide services was teetering on the brink of disaster when the reactor was finally restarted."

The report recommends ways to minimize the potential for shortages and to mitigate consequences for patients should a shortage occur, including better communications with doctors and the public and enhancing the capability of supplies to respond to shortages.

Related News

Portland General Electric Program Will Transform Hundreds of Homes Into a Virtual Power Plant

PGE Residential Energy Storage Pilot aggregates 525 home batteries into a virtual power plant, enabling distributed energy resources, smart grid control, renewable energy optimization, demand response, and backup power across Portland General Electric's area.

 

Key Points

A PGE program aggregating 525 batteries into a utility-run virtual power plant for renewables support and backup power.

✅ Up to 4 MW aggregated capacity from 525 residential batteries

✅ Monthly credits: $40 ($20 with solar) for grid services

✅ Enhances smart grid, DERs, resilience, and outage backup

 

Portland General Electric Company is set to launch a pilot program that will incentivize installation and connection of 525 residential energy storage batteries that PGE will dispatch, contributing up to four megawatts of energy to PGE's grid. The distributed assets will create a virtual power plant made up of small units that can be operated individually or combined to serve the grid, adding flexibility that supports PGE's transition to a clean energy future. When the program launches this fall, incentives will be available to residential customers across PGE's service area. Rebates will be available to customers within three neighborhoods participating in PGE's Smart Grid Test Bed, and income-qualified customers participating in Energy Trust of Oregon's Solar Within Reach offer.

PGE will study the full benefits of energy storage that these distributed energy assets can provide the grid while also increasing resiliency for each participating customer. PGE will operate and test the benefits of using homes' batteries, each capable of storing 12 to 16 kWh of energy, to optimize the use of renewable energy and grid capabilities. In the event of a power outage, participating customers can rely on them as a backup power resource.

"Our vision for clean energy relies on a smart, integrated grid. One of the ways that we'll achieve that is through creative partnerships and diversified energy resources, including those behind-the-meter," said Larry Bekkedahl, vice president of Grid Architecture, Integration and Systems Operation. "This pilot project will allow PGE to integrate even more intermittent renewable energy and enhance grid capabilities while also giving participating customers peace of mind in the event of an outage."

Energy storage maximizes renewables and the grid, improves power quality

Energy storage, including long-duration energy storage solutions, is vital to help capture and store energy from renewable power sources, such as wind and solar, that are more variable. As a virtual power plant, the residential battery storage pilot will create a single resource that can help the grid balance energy production with energy demand, freeing up the generation resources that are typically held on standby, ready to kick in when the wind doesn't blow or the sun doesn't shine. As a clean energy option that takes the place of standby resources, the virtual power plant also gives customers access to reliable energy, even in the event of system outages.

The test program will also allow PGE to test new smart-grid control devices across its distribution system that will more effectively allow a two-way exchange between PGE and pilot participants. The new controls will more actively manage the way that electricity is distributed across PGE's system to incorporate energy that customers generate, such as through solar panels, while also meeting power demand that is less predictable, such as for charging electric vehicles, supporting EVs for grid stability strategies. The controls will allow PGE to more actively manage power distribution to improve power quality for all customers.

Select rebates and incentives will be available to participants, aligned with electric vehicle programs that encourage transportation electrification

When it launches in fall 2020, participation in the program will be available to residential customers, including:

* Those across PGE's service area who already have or are installing a qualifying battery. Participation will require an application, and in exchange for allowing PGE to operate their battery for grid services, similar to programs where EV owners selling power back for compensation, participating customers will receive a monthly bill credit of $40, or $20 if the battery is charged with solar power.

* Customers across PGE's service area who are participating in the Solar Within Reach offering from Energy Trust of Oregon. Participants will be eligible for a $5,000 instant rebate in addition to the monthly bill credits.

* Those living within the PGE Smart Grid Test Bed who purchase a battery will be eligible for an instant rebate, in addition to the monthly bill credit of $40 or $20, which will allow PGE to test the localized grid impact of having a large concentration of battery storage devices available on one substation and explore interfaces with vehicle-to-grid pilots in the region.

PGE is working with Energy Trust to cost-effectively procure the residential battery storage systems, as utilities invest in advanced storage solutions across the region, by leveraging the existing Solar incentive program infrastructure and trade ally contractor network. Customers who participate in the program will own their battery systems, and rebates will only be available for systems installed by an Energy Trust solar trade ally. The program may also accept customers with a qualifying battery that is was previously installed, following a process to ensure safe operation.

More information about Portland General Electric's energy storage program is available at PortlandGeneral.com/energystorage and will be updated with details about the residential battery storage pilot program.

 

Related News

View more

IEC reaches settlement on Palestinian electricity debt

IEC-PETL Electricity Agreement streamlines grid management, debt settlement, and bank guarantees, shifting power supply, transmission, and distribution to PETL via IEC-built sub-stations, bolstering energy cooperation, utility billing, and payment assurance in PA areas.

 

Key Points

A 15-year deal transferring PA grid operations to PETL, settling legacy debt, and securing payments with bank guarantees.

✅ NIS 915 million repaid in 48 installments.

✅ PETL assumes distribution, O&M, and sub-station ownership.

✅ 15-year, NIS 2.8b per year supply and services contract.

 

The Palestinian Authority will pay Israel Electric NIS 915 million and take over management of its grid through Palestinian electricity supplier PETL.

The Israel Electric Corporation (IEC) (TASE: ELEC.B22) and Palestinian electricity supplier PETL have signed a draft commercial agreement under which the Palestinian Authority's (PA) debt of almost NIS 1 billion will be repaid. The agreement also transfers actual management of the supply of electricity to Palestinian customers from IEC to the Palestinian electricity authority, enabling consideration of distributed solutions such as a virtual power plant program in future planning.

Up until now, the IEC was unable to actually collect debts for electricity from Palestinian customers, because the connection with them was through the PA. Responsibility for collection will now be exclusively in Palestinian hands, with the PA providing hundreds of millions of shekels in bank guarantees for future debts. The agreement, which is valid for 15 years, amounts to an estimated NIS 2.8 billion a year, as of now.

IEC will sell electricity and related services to PETL through four high-tension sub-stations built by IEC for PETL and through high and low-tension connection points, similar to large interconnector projects like the Lake Erie Connector, for the purpose of distribution and supply of the electricity by PETL or an entity on its behalf to consumers in PA territory. PETL will have sole operational and maintenance responsibility for distribution and supply and ownership of the four sub-stations.

 

NIS 915 million in 48 payments

According to the IEC announcement, the settlement was reached following negotiations following the signing of an agreement in principle in September 2016 by the minister of finance, the government coordinator of activities in the territories, and the Palestinian minister for civilian affairs. The parties reached commercial understandings yesterday that made possible today's signing of the first commercial document of its kind regulating commercial relations - the sales of electricity - between the parties. The agreement will go into effect after it is approved by the IEC board of directors, the Public Utilities Authority (electricity), reflecting regulatory oversight akin to Ontario industrial electricity pricing consultations, and the IDF Chief Electrical Staff Officer. Representatives of IEC, the Ministry of Finance, the Public Utilities Authority (electricity), the government coordinator of activities in the territories, the civilian authority, the PA government, and PETL took part in the negotiations.

The agreement also settles the PA's historical debt to IEC. The PA will begin payment of NIS 915 million in debt for consumption of electricity before September 2016 to IEC Jerusalem District Ltd. in 48 equal installments after the final signing, as stipulated in the agreement in principle signed by the Israeli government and the PA on September 13, 2016.

The PA's debt for electricity amounted to almost NIS 2 billion in 2016. The initial spadework for the current debt settlement was accomplished in that year, after the parties reached understandings on writing off NIS 500 million of the Palestinian debt. The PA paid NIS 600 million in October 2016, and the remainder will be paid now.

It was also reported that an arrangement of securities and guarantees to ensure payment to IEC under the agreement had been settled, including the past debt. IEC will obtain a bank guarantee and a PA guarantee, in addition to the existing collection mechanisms at the company's disposal.

Minister of Finance Moshe Kahlon said, "Signing the commercial agreement is a historic step completing the agreement signed by the governments in September 2016. Strengthening economic cooperation between Israel and the PA is above all an Israeli security interest. The agreement will ensure future payments to the IEC and reinforce its financial position. I congratulate the negotiating teams for the completion of their task."

Minister of National Infrastructure, Energy, and Water Resources Dr. Yuval Steinitz said, "In my meeting last year with Palestinian Prime Minister Rami Hamdallah in Jenin, we agreed that it was necessary to settle the debt and formalize relations between IEC and the PA. The settlement signed today is a breakthrough, both in the measures for payment of the Palestinian debt to IEC and Israel and in arranging future relations to prevent more debts from emerging in the future. With the signing of the agreement, we will be able to make progress with the Palestinians in developing a modern electrical grid, aligning with regional initiatives like the Cyprus electricity highway, according to the model of the sub-station we inaugurated in Jenin."

IEC chairperson Yiftah Ron Tal said, "This is a historic event. In this agreement, IEC is correcting for the first time a historical distortion of accumulated debt without guarantees, ability to collect it, or control over the amount of debt. This anchor agreement not only constitutes an unprecedented financial achievement; it also constitutes an important milestone in regulating electricity commercial relations between the Israeli and Palestinian electric companies, comparable to cross-border efforts such as the Ireland-France interconnector in Europe."

 

Related News

View more

SDG&E Wants More Money From Customers Who Don’t Buy Much Electricity. A Lot More.

SDG&E Minimum Bill Proposal would impose a $38.40 fixed charge, discouraging rooftop solar, burdening low income households, and shifting grid costs during peak demand, as the CPUC weighs consumer impacts and affordability.

 

Key Points

Sets a $38.40 monthly minimum bill that raises low usage costs, deters rooftop solar, and burdens low income households.

✅ $38.40 fixed charge regardless of usage

✅ Disincentivizes rooftop solar investments

✅ Disproportionate impact on low income customers

 

The utility San Diego Gas & Energy has an aggressive proposal pending before the California Public Utilities Commission, amid recent commission changes in San Diego that highlight how regulatory decisions affect local customers: It wants to charge most residential customers a minimum bill of $38.40 each month, regardless of how much energy they use. The costs of this policy would hit low-income customers and those who generate their own energy with rooftop solar. We’re urging the Commission to oppose this flawed plan—and we need your help.

SDG&E’s proposal is bad news for sustainable energy. About half of the customers whose bills would go up under this proposal have rooftop solar. The policy would deter other customers from investing in rooftop solar by making these investments less economical. Ultimately, lost opportunities for solar would mean burning more gas in polluting power plants. 

The proposal is also bad news for people who already have to scrimp on energy costs. Most customers with big homes and billowing air conditioners won't notice if this policy goes into effect, because they use at least $38 worth of electricity a month anyway. But for households that don’t buy much electricity from the company, including those in small apartments without air conditioning, this proposal would raise the bills. Even for customers on special low-income rates, amid electric bill changes statewide, SDG&E wants a minimum bill of $19.20.

Penalizing customers who don’t use much electricity would disproportionately hurt lower-income customers, raising energy equity concerns across the region, who tend to use less energy than their wealthier neighbors. In the region SDG&E serves, the average family in an apartment uses half as much electricity as a single-family residence. Statewide, low-income households are more than four times as likely to be low-usage electricity customers than high-income households. When it gets hot, residential electricity patterns are often driven by air conditioning. The vast majority of SDG&E's customers live in the coastal climate zone, where access to air conditioning is strongly linked to income: Households with incomes over $150,000 are more than twice as likely to have air conditioning than families making less than $35,000, with significant racial disparities in who has AC.

In its attempt to rationalize its request, SDG&E argues that it should charge everyone for infrastructure costs that do not depend on how much energy they use. But the cost of the grid is driven by how much energy SDG&E delivers on hot summer afternoons, when some customers blast their AC and demand for electricity peaks. If more customers relied on their own solar power or conserved energy, the utility would spend less on its grid and help rein in soaring electricity prices over time.

In the long term, reducing incentives to go solar and conserve energy will strain the grid and drive up costs for everyone, especially as lawmakers may overturn income-based charges and reshape rate design. SDG&E's arguments are part of a standard utility playbook for trying to hike income-based fixed charges, and consumer advocates have repeatedly shut them down.  As far as we know, no regulators in the country have allowed a utility to charge customers over $38 for the “privilege” of accessing electric service. 

 

Related News

View more

Sen. Cortez Masto Leads Colleagues in Urging Congress to Support Clean Energy Industry in Economic Relief Packages

Clean Energy Industry Support includes tax credits, refundability, safe harbor extensions, EV incentives, and stimulus measures to stabilize renewable energy projects, protect the workforce, and ensure financing continuity during economic recovery.

 

Key Points

Policies and funding to stabilize renewables, protect jobs, and extend tax incentives for workforce continuity.

✅ Extend PTC/ITC and remove phase-outs to sustain projects

✅ Enable direct pay or refundability to unlock financing

✅ Preserve safe harbor timelines disrupted by supply chains

 

U.S. Senator Catherine Cortez Masto (D-Nev.) led 17 Senate colleagues, as the Senate moves to modernize public-land renewables, in sending a letter calling on Congress to include support for the United States' clean energy industry and workforce in any economic aid packages.

"As Congress takes steps to ensure that our nation's workforce is prepared to emerge stronger from the coronavirus health and economic crisis, we must act to shore up clean energy businesses and workers who are uniquely impacted by the crisis, echoing a power-sector call for action from industry groups," said the senators. "This action, which has precedent in prior financial recovery efforts, could take several forms, including tax credit extensions or removal of the current phase-out schedule, direct payment or refundability, or extensions of safe harbor continuity."

"We need to make sure that any package protects workers and helps families stay afloat in these challenging times. Providing support to the clean energy industry will give much-needed certainty and confidence, as the sector targets a market majority, for those workers that they will be able to keep their paychecks and their jobs in this critical industry," the senators also said.

In addition to Senator Cortez Masto, the letter was also signed by Senators Ed Markey (D-Mass.), Martin Heinrich (D-N.M), Sheldon Whitehouse (D-R.I.), Debbie Stabenow (D-Mich.), Tina Smith (D-Minn.), Jack Reed (D-R.I.), Cory Booker (D-N.J.), Richard Blumenthal (D-Conn.), Amy Klobuchar (D-Minn.), Chris Van Hollen (D-Md.), Dianne Feinstein (D-Calif.), Jacky Rosen (D-Nev.), Tammy Duckworth (D-Ill.), Chris Coons (D-Del.), Mazie Hirono (D-Hawaii), Dick Durbin (D-Ill.), and Kyrsten Sinema (D-Ariz.).

Dear Leader McConnell, Leader Schumer, Chairman Grassley, Ranking Member Wyden:

As Congress takes steps to ensure that our nation's workforce is prepared to emerge stronger from the coronavirus health and economic crisis, we must act to shore up clean energy businesses and workers who are uniquely impacted by the crisis, with wind investments at risk amid the pandemic. This action, which has precedent in prior financial recovery efforts, could take several forms, including tax credit extensions or removal of the current phase-out schedule, direct payment or refundability, or extensions of safe harbor continuity.

First and foremost, we need to take care of workers' health and immediate needs to stay in their homes and provide for their families, and the Families First Coronavirus Response Act is a critical down payment. Now, we must make sure the workforce has jobs to return to and that employers remain able to pay for critical benefits like paid sick and family leave, healthcare, and Unemployment Insurance.

The renewable energy industry employs over 800,000 people across every state in the United States. This industry and its workers could suffer significant harms as a result of the coronavirus emergency and resulting financial impact. Renewable energy businesses are already seeing project cancellations or delays, as the Covid-19 crisis hits solar and wind across the sector, with the solar industry reporting delays of 30 percent. Likewise, the energy efficiency sector is susceptible to similar impacts. As the coronavirus pandemic intensifies in the United States, that rate of delay or cancellations will only continue to skyrocket. Global and domestic supply chains are already facing chaotic changes, with equipment delays of three to four months for parts of the industry. A major collapse in financing is all but certain as investment firms' profits turn to losses and capital is suddenly unavailable for large labor-intensive investments.

To ensure that we do not lose years of progress on clean energy and the source of employment for tens of thousands of renewable energy workers, Congress should look to previous relief packages as an example for how to support this sector and the broader American economy. The American Recovery and Reinvestment Act of 2009 (also known as the Recovery Act or ARRA) provided over $90 billion in funding for clean energy and grid modernization, along with emergency relief programs. Specifically, ARRA provided immediate funding streams like the 1603 Cash Grant program for renewables and the 30 percent clean energy manufacturing tax credit to give immediate relief for the clean energy industry. As Congress develops this new package, it should consider these immediate relief programs for the renewable and clean energy industry, especially as analyses suggest green energy could drive Covid-19 recovery at scale. This could include direct payment or refundability, extensions of safe harbor continuity, tax credit extensions, electric vehicle credit expansion, or removal of the current phase-out schedules for the clean energy industry.

We need to make sure that any package protects workers and helps families stay afloat in these challenging times. Providing support to the clean energy industry will give much-needed certainty and confidence for those workers that they will be able to keep their paychecks and their jobs in this critical industry.

These strategies to provide assistance to the clean energy industry must be included in any financial recovery discussions, particularly if the Trump Administration continues its push to aid the oil industry, even as some advocate a total fossil fuel lockdown to accelerate climate action. We appreciate your consideration and collaboration as we do everything in our power to quickly recover from this health and economic emergency.

 

Related News

View more

A New Era for Churchill Falls: Newfoundland and Labrador Secures Billions in Landmark Deal with Quebec

Churchill Falls NL-Quebec Agreement boosts hydropower revenues, revises power purchase pricing, expands transmission lines, and integrates Indigenous rights, enabling renewable energy growth, domestic supply, exports, and interprovincial collaboration on infrastructure and utility modernization.

 

Key Points

A renegotiated hydropower deal reallocating power and advancing projects with Indigenous benefits in NL and Quebec.

✅ Raises Hydro-Quebec price for Churchill Falls electricity

✅ Increases NL power share for domestic use and exports

✅ Commits joint projects and Indigenous participation safeguards

 

St. John's, Newfoundland and Labrador - In a historic development, Newfoundland and Labrador (NL) and Quebec have reached a tentative agreement over the controversial Churchill Falls hydroelectric project, amid Quebec's electricity ambitions and longstanding regional sensitivities, potentially unlocking hundreds of billions of dollars for the Atlantic province. The deal, announced jointly by Premier Andrew Furey and Quebec Premier François Legault, aims to rectify the decades-long imbalance in the original 1969 contract, which saw NL receive significantly less revenue than Quebec for the province's vast hydropower resources.

The core of the new agreement involves a substantial increase in the price that Hydro-Québec pays for electricity generated at Churchill Falls. This price hike, retroactive to January 1, 2025, is expected to generate billions in additional revenue for NL over the next several decades. The deal also includes provisions for:

  • Increased power allocation for NL: The province will gain a larger share of the electricity generated at Churchill Falls, allowing for increased domestic consumption and potential export opportunities through the sale and trade of power across regional markets.
  • Joint infrastructure development: Both provinces will collaborate on new energy projects, in line with Hydro-Québec's $185-billion plan to reduce fossil fuel reliance, including potential expansions to the Churchill Falls generating station and the development of new transmission lines.
  • Indigenous involvement: The agreement acknowledges the importance of Indigenous rights and seeks to ensure that Indigenous communities in both provinces benefit from the project.

This landmark deal represents a significant victory for NL, which has long argued that the original 1969 contract was grossly unfair. The province has been seeking to renegotiate the terms of the agreement for decades, citing the low price paid for electricity and the significant economic benefits that have accrued to Quebec.

Key Implications:

  • Economic Transformation: The influx of revenue from the new Churchill Falls agreement has the potential to significantly transform the economy of NL, though the legacy of Muskrat Falls costs tempers expectations before plans are finalized. The province can invest in critical infrastructure projects, such as healthcare, education, and transportation, as well as support economic diversification initiatives.
  • Energy Independence: The increased access to electricity will enhance NL's energy security and reduce its reliance on fossil fuels. This shift towards renewable energy aligns with the province's climate change goals, and in the context of Quebec's no-nuclear stance could attract new investment in sustainable industries.
  • Interprovincial Relations: The successful negotiation of this complex agreement demonstrates the potential for constructive collaboration between provinces on major infrastructure projects, as seen in recent NB Power-Hydro-Québec agreements to import more electricity. It sets a precedent for future interprovincial partnerships on issues of shared interest.

Challenges and Considerations:

  • Implementation: The successful implementation of the agreement will require careful planning and coordination between the two provinces.
  • Environmental Impact: The expansion of hydroelectric generation at Churchill Falls must be carefully assessed for its potential environmental impacts, including the effects on local ecosystems and Indigenous communities.
  • Public Consultation: It is crucial that the governments of NL and Quebec engage in meaningful public consultation throughout the implementation process to ensure that the benefits of the agreement are shared equitably across both provinces.

The Churchill Falls agreement marks a turning point in the history of energy development in Canada. It demonstrates the potential for provinces to work together to achieve mutually beneficial outcomes, even as Nova Scotia shifts toward wind and solar after stepping back from the Atlantic Loop, while also addressing historical inequities and ensuring a more equitable distribution of the benefits of natural resources.

 

Related News

View more

Cheap material converts heat to electricity

Polycrystalline Tin Selenide Thermoelectrics enable waste heat recovery with ZT 3.1, matching single crystals while cutting costs, powering greener car engines, industrial furnaces, and thermoelectric generators via p-type and emerging n-type designs.

 

Key Points

Low-cost tin selenide devices that turn waste heat into power, achieving ZT 3.1 and enabling p-type and n-type modules.

✅ Oxygen removal prevents heat-leaking tin oxide grain skins.

✅ Polycrystalline ingots match single-crystal ZT 3.1 at lower cost.

✅ N-type tin selenide in development to pair with p-type.

 

So-called thermoelectric generators turn waste heat into electricity without producing greenhouse gas emissions, providing what seems like a free lunch. But despite helping power the Mars rovers, the high cost of these devices has prevented their widespread use. Now, researchers have found a way to make cheap thermoelectrics that work just as well as the pricey kind. The work could pave the way for a new generation of greener car engines, industrial furnaces, and other energy-generating devices.

“This looks like a very smart way to realize high performance,” says Li-Dong Zhao, a materials scientist at Beihang University who was not involved with the work. He notes there are still a few more steps to take before these materials can become high-performing thermoelectric generators. However, he says, “I think this will be used in the not too far future.”

Thermoelectrics are semiconductor devices placed on a hot surface, like a gas-powered car engine or on heat-generating electronics using thin-film converters to capture waste heat. That gives them a hot side and a cool side, away from the hot surface. They work by using the heat to push electrical charges from one to the other, a process of turning thermal energy into electricity that depends on the temperature gradient. If a device allows the hot side to warm up the cool side, the electricity stops flowing. A device’s success at preventing this, as well as its ability to conduct electrons, feeds into a score known as the figure of merit, or ZT.

 Over the past 2 decades, researchers have produced thermoelectric materials with increasing ZTs, while related advances such as nighttime solar cells have broadened thermal-to-electric concepts. The record came in 2014 when Mercouri Kanatzidis, a materials scientist at Northwestern University, and his colleagues came up with a single crystal of tin selenide with a ZT of 3.1. Yet the material was difficult to make and too fragile to work with. “For practical applications, it’s a non-starter,” Kanatzidis says.

So, his team decided to make its thermoelectrics from readily available tin and selenium powders, an approach that, once processed, makes grains of polycrystalline tin selenide instead of the single crystals. The polycrystalline grains are cheap and can be heated and compressed into ingots that are 3 to 5 centimeters long, which can be made into devices. The polycrystalline ingots are also more robust, and Kanatzidis expected the boundaries between the individual grains to slow the passage of heat. But when his team tested the polycrystalline materials, the thermal conductivity shot up, dropping their ZT scores as low as 1.2.

In 2016, the Northwestern team discovered the source of the problem: an ultrathin skin of tin oxide was forming around individual grains of polycrystalline tin selenide before they were pressed into ingots. And that skin acted as an express lane for the heat to travel from grain to grain through the material. So, in their current study, Kanatzidis and his colleagues came up with a way to use heat to drive any oxygen away from the powdery precursors, leaving pristine polycrystalline tin selenide, whereas other devices can generate electricity from thin air using ambient moisture.

The result, which they report today in Nature Materials, was not only a thermal conductivity below that of single-crystal tin selenide but also a ZT of 3.1, a development that echoes nighttime renewable devices showing electricity from cold conditions. “This opens the door for new devices to be built from polycrystalline tin selenide pellets and their applications to be explored,” Kanatzidis says.

Getting through that door will still take some time. The polycrystalline tin selenide the team makes is spiked with sodium atoms, creating what is known as a “p-type” material that conducts positive charges. To make working devices, researchers also need an “n-type” version to conduct negative charges.

Zhao’s team recently reported making an n-type single-crystal tin selenide by spiking it with bromine atoms. And Kanatzidis says his team is now working on making an n-type polycrystalline version. Once n-type and p-type tin selenide devices are paired, researchers should have a clear path to making a new generation of ultra-efficient thermoelectric generators. Those could be installed everywhere from automobile exhaust pipes to water heaters and industrial furnaces to scavenge energy from some of the 65% of fossil fuel energy that winds up as waste heat. 

 

Related News

View more

Sign Up for Electricity Forum’s Newsletter

Stay informed with our FREE Newsletter — get the latest news, breakthrough technologies, and expert insights, delivered straight to your inbox.

Electricity Today T&D Magazine Subscribe for FREE

Stay informed with the latest T&D policies and technologies.
  • Timely insights from industry experts
  • Practical solutions T&D engineers
  • Free access to every issue

Live Online & In-person Group Training

Advantages To Instructor-Led Training – Instructor-Led Course, Customized Training, Multiple Locations, Economical, CEU Credits, Course Discounts.

Request For Quotation

Whether you would prefer Live Online or In-Person instruction, our electrical training courses can be tailored to meet your company's specific requirements and delivered to your employees in one location or at various locations.