Compact Medium-Voltage Converters To Enable Advanced Grid Architectures & Operations
As we trend toward more renewables and distributed energy resources (DERs), the design of the electric distribution system itself imposes physical limitations. These system constraints could lead to issues like overloaded power lines and faults that propagate freely.
But what if we could restructure the underlying system to support greater renewable integration and system resilience? To that end, a National Renewable Energy Laboratory (NREL)–led project is working on a new type of grid device enabled by silicon carbide (SiC) switches and other medium voltage (MV) power electronics that could segment sections of the grid, providing advanced control for flexibility and resilience for our power systems.
The project team is first designing a megawatt-scale prototype converter that provides native “back-to-back” conversion — AC to AC power — at distribution voltages (i.e., not requiring transformers to step down voltage to levels typically used in electronic power conversion). By using MV SiC-based power modules, the converters could be 1/5th the size and 1/10th the weight of alternate equivalent systems, which are trailer-sized and include heavy transformers. Then the team will connect the power converter into NREL’s MV testbed to validate new grid control approaches that the prototype enables.
The project is named “Grid Application Development, Testbed, and Analysis for MV SiC (GADTAMS)” and is funded by the Department of Energy’s Advanced Manufacturing Office.
The NREL-led GADTAMS project is developing and demonstrating smaller and lighter alternatives for direct medium-voltage connections on the grid, which could enable new resilient grid architectures.
“With back-to-back converters between feeders, we can go one step higher in providing resilience across the distribution system,” said Akanksha Singh, a project lead at NREL.
“This technology wasn’t necessary before because we didn’t have so many distributed energy resources on the system, but now we have feeders that are becoming saturated with PV; apart from storage, these feeders don’t have anywhere to inject that excess power,” Singh said. “A new approach to grid interconnection could enable advanced forms of power sharing and provide much-enhanced grid resilience.”
A future grid that features such converters would have the capability to control the flow of power between sections of the grid, shunting excess load or DER-based generation to feeder sections or adjacent circuits as needed, adding new versatility to power distribution. Networked microgrids could protect against the propagation of faults from one microgrid to the next while still allowing controlled power dispatch between the two systems and the macrogrid as well.
During outage recovery, microgrids could be formed that then stabilize neighboring microgrid systems, as envisioned in NREL’s autonomous energy systems research. In general, the two sides of the converter do not need to be synchronized in frequency or even exact voltage level at all — a major shift from the modern power system. But prior to proving any of these applications, NREL and others will first need to build the necessary controls.
“We are developing very novel controls for upcoming grid architectures,” Singh said. “We have local controls on inverters, and we have hierarchical controls that coordinate between grid partitions. With regard to grid support, these controls can do it all: dynamic stability, frequency support, black start, fault ride-through and protection.”
Unlike anything currently available, the NREL testbed provides an environment to validate medium-voltage grid solutions with real power hardware-in-the-loop and real-time grid simulation. For this project, NREL and partners are interested in the full range of use cases for back-to-back SiC converters and have teamed with utility Southern California Edison to inform on utility applications, as well as industry partners General Atomics and Eaton to seek out a commercial path for the technology.
The SiC converter is being built in two halves by project partners Ohio State University and Florida State University. The three-phase converter prototype will be rated for 330 kW and will implement a full thermal and electrical design appropriate for utility use. Traditionally, the same AC-to-AC conversion process requires stepping-down the voltage to low-voltage levels where conventional power electronics can be used, which results in heavy and expensive transformer equipment. The MV SiC option takes advantage of the superior voltage ratings of devices to minimize weight, cost, and size, which makes the technology far more practical and economical for system-wide deployment.
Still, the converter technology is only one aspect of fulfilling flexible interconnections. This framework currently lacks the standardization that exists for so many other recent grid innovations. At NREL, the project team hopes to collect baseline operational data to jumpstart the conversation around how to integrate MV converters in future grids.
“This is a new application that doesn’t exist anywhere yet. We need standards that apply to how the converters can integrate with regular system operation, like starting up, syncing to the grid, etc.,” Singh said. “We are using IEEE Standards 1547 and 2030.8 as a base, interpreting their rules to implement new controls on MV systems. We are trying to merge the two to understand what will apply to this new approach.”
An entirely new grid architecture and operational flexibility could seem far-out for now, but NREL and partners are showing that these options are viable in the near-term and that NREL has the capability to prepare these solutions for real systems. Learn more about how NREL can validate advanced energy systems at scale.
Article courtesy of NREL.
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Environment
Why OPEC+ is accelerating oil production as prices are tanking and tariffs hammer markets
The Phillips 66 Company’s Los Angeles Refinery in California.
Bing Guan | Reuters
The oil price outlook is being hit with more bearish forecasts on the back of U.S. President Donald Trump’s sweeping and market-hammering tariff announcements. Businesses and investors worry that a trade war and lower global growth lies ahead.
Goldman Sachs on Thursday reduced its December 2025 forecasts for global and U.S. benchmarks Brent crude and WTI by $5 to $66 and $62 a barrel, respectively, “because the two key downside risks we have flagged are realizing, namely tariff escalation and somewhat higher OPEC+ supply.”
The bank also cut its forecasts for the oil benchmarks in 2025 and 2026, adding that “we no longer forecast a price range, because price volatility is likely to stay elevated on higher recession risk.” Analysts at S&P Global Market Intelligence predict that in a worst-case scenario, global oil demand growth could be slashed by 500,000 barrels per day.
JPMorgan, for its part, raised its recession odds for the global economy to 60% for this year, up from a previous forecast of 40%.
Markets were therefore stunned when OPEC, which produces about 40% of the world’s crude oil — along with its non-OPEC allies that together comprise OPEC+ — chose not only to go ahead with its previously held plans to increase oil production, but also to nearly triple the expected increase figure.
Eight key OPEC+ producers on Thursday agreed to raise combined crude oil output by 411,000 barrels per day, speeding up the pace of their scheduled hikes and pushing down oil prices. The group — Saudi Arabia, Russia, Iraq, the United Arab Emirates, Kuwait, Kazakhstan, Algeria, and Oman — was widely expected to implement an increase of just under 140,000 barrels per day next month.
The news pushed oil prices 6% lower.
OPEC+ bullishness and appeasing Trump
Several factors underpin the oil-producing alliance’s decision. One is that the group is bullish on oil demand later in the year, putting it firmly in the minority as investor outlooks sour and fears of a global slowdown worsen.
The eight OPEC+ members behind the production decision cited “the continuing healthy market fundamentals and the positive market outlook” in their statement Thursday, saying that “this measure will provide an opportunity for the participating countries to accelerate their compensation.”
The statement added that “the gradual increases may be paused or reversed subject to evolving market conditions.”
Another likely reason for the group’s move has to do with another T-word: the man in the White House, who during his first term in office and from the very start of his second, has loudly demanded that the oil producer group pump more crude to help bring down prices for Americans.
“First of all, this is partly about appeasing Trump,” Saul Kavonic, head of energy research at MST Marquee, told CNBC’s Dan Murphy on Friday.
“Trump will be putting pressure on OPEC to reduce oil prices, which reduces global energy prices, to help offset the inflationary impact of his tariffs.”
OPEC officials have denied that the move was made to appease Trump.
Compliance and market share
Meanwhile, as compliance is a major issue for OPEC+ — with countries overproducing crude beyond their quotas, complicating the group’s efforts to control how much supply it allows into the market — the move could be a way to enforce that, according to Helima Croft, head of global commodity strategy and MENA research at RBC Capital Markets.
“We think a desire by the OPEC leadership to send a warning signal to Kazakhstan, Iraq, and even Russia about the cost of continued overproduction underlies the decision.”
Helima Croft
head of global commodity strategy and MENA research at RBC Capital Markets
“We think a desire by the OPEC leadership to send a warning signal to Kazakhstan, Iraq, and even Russia about the cost of continued overproduction underlies the decision,” Croft wrote in a note published Thursday. She referenced the March 2020 oil price war, when Saudi Arabia flooded the market with supply to tank oil prices and forced Russia back into compliance after Moscow initially refused to curb production to help the alliance stabilize prices. The price war caused Brent crude prices to go as low as $15 a barrel.
The production increases are also “an example of OPEC increasing their market share,” Kavonic said, adding that it “ultimately does come at the expense of the United States [shale] patch,” which U.S. producers likely will not be too thrilled about.
What happens next?
OPEC+ appears confident about the market turning a corner in the coming months on the assumption that oil demand will increase in the summer and the tariff wars will be resolved in the coming months, said Nader Itayim, editorial manager at Argus Media.
“These countries are largely comfortable with the $70, $75 per barrel band,” Itayim said.
What comes next depends on the trajectory of the tariffs and a potential trade war. Oil dropping into the $60 range could force pauses or even a reversal in OPEC+ production increase plans, analysts say – although that is likely to be met with resistance from countries like Iraq and Kazakhstan that have long been itching to increase their oil production for their own revenues.
Whatever happens, the group maintains the flexibility to adapt its plans month by month, Itayim noted.
“If things don’t quite go the way they imagine, all it does take, really, is a phone call.”
According to a Tesla Semi customer, the electric truck program is suffering more delays and a price increase that is described as “dramatic.”
Tesla Semi has seen many delays, more than any other vehicle program at Tesla.
It was initially unveiled in 2017, and CEO Elon Musk claimed that it would go into production in 2019.
In late 2022, Tesla held an event where it unveiled the “production version” of the Tesla Semi and delivered the first few units to a “customer-partner”: PepsiCo.
More than 3 years later, the vehicle never went into volume production. Instead, Tesla only ran a very low volume pilot production at a factory in Nevada and only delivered a few dozen trucks to customers as part of test programs.
But Tesla promised that things would finally happen for the Tesla Semi this year.
Tesla has been building a new high-volume production factory specifically for the Tesla Semi program in a new building next to Gigafactory Nevada.
The goal was to start production in 2025, start customer deliveries, and ramp up to 50,000 trucks yearly.
Now, Ryder, a large transportation company and early customer-partner in Tesla’s semi truck program, is talking about further delays. The company also refers to a significant price increase.
California’s Mobile Source Air Pollution Reduction Review Committee (MSRC) awarded Ryder funding for a project to deploy Tesla Semi trucks and Megachargers at two of its facilities in the state.
Ryder had previously asked for extensions amid the delays in the Tesla Semi program.
In a new letter sent to MSRC last week and obtained by Electrek, Ryder asked the agency for another 28-month delay. The letter references delays in “Tesla product design, vehicle production” and it mentions “dramatic changes to the Tesla product economics”:
This extension is needed due to delays in Tesla product design, vehicle production and dramatic changes to the Tesla product economics. These delays have caused us to reevaluate the current Ryder fleet in the area.
The logistics company now says it plans to “deploy 18 Tesla Semi vehicles by June 2026.”
The reference to “dramatic changes to the Tesla product economics” points to a significant price increase for the Tesla Semi, which further communication with MSRC confirms.
In the agenda of a meeting to discuss the extension and changes to the project yesterday, MSRC confirms that the project went from 42 to 18 Tesla Semi trucks while the project commitment is not changing:
Ryder has indicated that their electric tractor manufacturer partner, Tesla, has experienced continued delays in product design and production. There have also been dramatic changes to the product economics. Ryder requests to reduce the number of vehicles from 42 to 18, stating that this would maintain their $7.5 million private match commitment.
In addition to the electric trucks, the project originally involved installing two integrated power centers and four Tesla Megachargers, split between two locations. Ryder is also looking to now install 3 Megachargers per location for a total of 6 instead of 4.
The project changes also mention that “Ryder states that Tesla now requires 600kW chargers rather than the 750kW units originally engineered.”
Tesla Semi Price
When originally unveiling the Tesla Semi in 2017, the automaker mentioned prices of $150,000 for a 300-mile range truck and $180,000 for the 500-mile version. Tesla also took orders for a “Founder’s Series Semi” at $200,000.
However, Tesla didn’t update the prices when launching the “production version” of the truck in late 2023. Price increases have been speculated, but the company has never confirmed them.
New diesel-powered Class 8 semi trucks in the US today often range between $150,000 and $220,000.
The combination of a reasonable purchase price and low operation costs, thanks to cheaper electric rates than diesel, made the Tesla Semi a potentially revolutionary product to reduce the overall costs of operation in trucking while reducing emissions.
However, Ryder now points to a “dramatic” price increase for the Tesla Semi.
What is the cost of a Tesla Semi electric truck now?
Electrek’s Take
As I have often stated, Tesla Semi is the vehicle program I am most excited about at Tesla right now.
If Tesla can produce class 8 trucks capable of moving cargo of similar weight as diesel trucks over 500 miles on a single charge in high volume at a reasonable price point, they have a revolutionary product on their hands.
But the reasonable price part is now being questioned.
After reading the communications between Ryder and MSRC, while not clear, it looks like the program could be interpreted as MSRC covering the costs of installing the charging stations while Ryder committed $7.5 million to buying the trucks.
The math makes sense for the original funding request since $7.5 million divided by 42 trucks results in around $180,000 per truck — what Tesla first quoted for the 500-mile Tesla Semi truck.
Now, with just 18 trucks, it would point to a price of $415,000 per Tesla Semi truck. It’s possible that some of Ryder’s commitment could also go to an increase in Megacharger prices – either per charger or due to the two additional chargers. MSRC said that they don’t give more money when prices go up after an extension.
I wouldn’t be surprised if the 500-mile Tesla Semi ends up costing $350,000 to $400,000.
If that’s the case, Tesla Semi is impressive, but it won’t be the revolutionary product that will change the trucking industry.
It will need to be closer to $250,000-$300,000 to have a significant impact, which is not impossible with higher-volume production but would be difficult.
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