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As communities, cities, and states develop ambitious energy efficiency and decarbonization goals, energy storage is an increasingly critical component of our energy economy. Renewable energy sources like solar and wind are changing how we power our buildings, industries, and grid; however, they are intermittent ― we need continuous power even after the sun sets or the wind dies down. As such, energy storage is critical to ensuring continuous power and allows energy producers to take full advantage during times of overgeneration on sunny (or windy) days.

When it comes to short-duration energy storage, lithium-ion batteries are considered the front-runner, but batteries are not the whole story. Our buildings, businesses, industries, and grid need more storage, at lower cost, for longer durations, and at larger capacities than batteries can provide to displace fossil fuels for a sustainable future.

To meet this energy storage challenge, researchers at the National Renewable Energy Laboratory (NREL) are in the late stages of prototype testing a game-changing new thermal energy storage technology that uses inexpensive silica sand as a storage medium. Economic Long-Duration Electricity Storage by Using Low-Cost Thermal Energy Storage and High-Efficiency Power Cycle (ENDURING) is a reliable, cost-effective, and scalable solution that can be sited anywhere.

The ENDURING Mechanism: Storable, Electrically Heated Sand Delivers On-Demand Electricity

ENDURING uses electricity from surplus solar or wind to heat a thermal storage material — silica sand. Particles are fed through an array of electric resistive heating elements to heat them to 1,200°C (imagine pouring sand through a giant toaster). The heated particles are then gravity-fed into insulated concrete silos for thermal energy storage. The baseline system is designed for economical storage of up to a staggering 26,000 MWh of thermal energy. With modular design, storage capacity can be scaled up or down with relative ease.

Particle thermal energy storage systems can be constructed with existing infrastructure from retired coal and gas power plants. Image by Al Hicks and Besiki Kazaishvili, NREL

When energy is needed, the hot particles are gravity-fed through a heat exchanger, heating and pressurizing a working gas inside to drive the turbomachinery and spin generators that create electricity for the grid. The system discharges during periods of high electricity demand and when limited solar photovoltaic or wind power are available, such as early in the morning and evening, during dinner preparation, and when TVs are on. Once discharged, the spent, cold particles are once again fed into insulated silos for storage until conditions (and economics) are appropriate again for charging.

How Hot Sand in a Silo Is Revolutionizing Energy Decarbonization

ENDURING offers several advantages relative to other electricity storage technologies.

As a storage medium, abundant silica sand is stable and inexpensive at $30‒$50/ton, and has a limited ecological impact both in extraction and end of life. For comparison, lithium-ion batteries have an exceptional energy storage density ― important for certain sectors such as transportation, where weight matters ― but it comes at a high cost. Particle thermal energy storage is a less energy dense form of storage, but is very inexpensive ($2‒$4 per kWh of thermal energy at a 900°C charge-to-discharge temperature difference). The energy storage system is safe because inert silica sand is used as storage media, making it an ideal candidate for massive, long-duration energy storage.

ENDURING systems have no particular siting constraints and can be located anywhere in the country. These systems may also be constructed using existing infrastructure from retired coal- and gas-fired power plants.

ENDURING technology can support the expansion of renewable energy generation across our country. Building these cost-effective particle thermal energy storage systems around the United States could help utilities to continue using solar and wind without running the risk of destabilizing the grid or needing to curtail renewable energy generation. Particle thermal energy storage will also provide energy reserves so our communities can better navigate through extended weather events, whether a week-long cold front or a summer heat wave.

Multiple Potential Economical Use Cases Support Decarbonization by 2050

The Biden Administration seeks to achieve a carbon-free power sector by 2035 and a net zero emissions economy by 2050. Zhiwen Ma, principal investigator of the ENDURING project, sees an important role for particle thermal energy storage in achieving these goals. “While decarbonization of electricity has a clear path, decarbonization of the whole economy ― which includes things like building heat and industrial processes ― is more challenging because natural gas is very cheap, making it hard to displace,” he said. “Decarbonizing industrial processes and building heat is very tough.”

Converting renewable electricity into heat is one way to decarbonize these sectors. Ma sees an opportunity for particle thermal energy storage to play a role in cost-effectively supplanting natural gas. By using a heat pump, one unit of electricity is transformed into two to three units of heat, which can be stored in the particle thermal energy storage system and then later delivered to the end user (depending on the coefficient of performance of the heat pump or the use of an emerging pumped thermal energy storage technology). These technologies can be used for building and industry process heating to replace coal or natural gas.

In addition to providing grid storage and building heat, ENDURING offers a steady source of heat for industrial and chemical processes that are otherwise incompatible with the intermittency associated with solar and wind power.

According to NREL researcher Patrick Davenport, the economic environment, decarbonization goals, and technology have aligned for particle thermal energy storage. “Sand and concrete silos with refractory insulation are very inexpensive materials that can lead to low-cost energy storage,” he said. “Traditional four-hour storage technologies don’t scale well to the grid or city scale. Now that we are in need of large-scale energy storage, this technology makes a lot of sense.”

Early Achievements and ENDURING Promise

The ENDURING project is seeing promising progress and early interest. The team recently won the American Society of Mechanical Engineers Advanced Energy Systems Division and Solar Energy Division 2021 First-Place Best Paper Award and several U.S. Department of Energy technology funding awards. Patents on concentrating solar power integration have been awarded, and several more are being filed.

The ENDURING prototype heaters and heat exchangers are currently undergoing testing in high-temperature conditions. If the prototype tasks are successful this fall, Ma is confident that ENDURING technology will offer great potential to support renewable integration for future carbon-free energy supply.

Ma is not the only one who sees promise: NREL and clean-energy technology firm Babcock & Wilcox have an exclusive intellectual property option agreement to license the ENDURING particle thermal energy storage technology. Babcock & Wilcox are among several industry and academic research partners that contributed to the ENDURING project, including General Electric, Allied Mineral Products, Worley, Purdue University, and Colorado School of Mines.

Learn more about NREL thermal systems and concentrating solar power research.

Article courtesy of NREL.

 

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Robinhood is up 160% this year, but several obstacles are ahead

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Robinhood is up 160% this year, but several obstacles are ahead

Florida AG opens probe into Robinhood. Here's the latest

Robinhood stock hit an all-time high Friday as the financial services platform continued to rip higher this year, along with bitcoin and other crypto stocks.

Robinhood, up more than 160% in 2025, hit an intraday high above $101 before pulling back and closing slightly lower.

The reversal came after a Bloomberg report that JPMorgan plans to start charging fintechs for access to customer bank data, a move that could raise costs across the industry.

For fintech firms that rely on thin margins to offer free or low-cost services to customers, even slight disruptions to their cost structure can have major ripple effects. PayPal and Affirm both ended the day nearly 6% lower following the report.

Despite its stellar year, the online broker is facing several headwinds, with a regulatory probe in Florida, pushback over new staking fees and growing friction with one of the world’s most high-profile artificial intelligence companies.

Florida Attorney General James Uthmeier opened a formal investigation into Robinhood Crypto on Thursday, alleging the platform misled users by claiming to offer the lowest-cost crypto trading.

“Robinhood has long claimed to be the best bargain, but we believe those representations were deceptive,” Uthmeier said in a statement.

The probe centers on Robinhood’s use of payment for order flow — a common practice where market makers pay to execute trades — which the AG said can result in worse pricing for customers.

Robinhood Crypto General Counsel Lucas Moskowitz told CNBC its disclosures are “best-in-class” and that it delivers the lowest average cost.

“We disclose pricing information to customers during the lifecycle of a trade that clearly outlines the spread or the fees associated with the transaction, and the revenue Robinhood receives,” added Moskowitz.

Robinhood CEO Vlad Tenev explains 'dual purpose' behind trading platform's new crypto offerings

Robinhood is also facing opposition to a new 25% cut of staking rewards for U.S. users, set to begin October 1. In Europe, the platform will take a smaller 15% cut.

Staking allows crypto holders to earn yield by locking up their tokens to help secure blockchain networks like ethereum, but platforms often take a percentage of those rewards as commission.

Robinhood’s 25% cut puts it in line with Coinbase, which charges between 25.25% and 35% depending on the token. The cut is notably higher than Gemini’s flat 15% fee.

It marks a shift for the company, which had previously steered clear of staking amid regulatory uncertainty.

Under President Joe Biden‘s administration, the Securities and Exchange Commission cracked down on U.S. platforms offering staking services, arguing they constituted unregistered securities.

With President Donald Trump in the White House, the agency has reversed course on several crypto enforcement actions, dropping cases against major players like Coinbase and Binance and signaling a more permissive stance.

Even as enforcement actions ease, Robinhood is under fresh scrutiny for its tokenized stock push, which is a growing part of its international strategy.

The company now offers blockchain-based assets in Europe that give users synthetic exposure to private firms like OpenAI and SpaceX through special purpose vehicles, or SPVs.

An SPV is a separate entity that acquires shares in a company. Users then buy tokens of the SPV and don’t have shareholder privileges or voting rights directly in the company.

OpenAI has publicly objected, warning the tokens do not represent real equity and were issued without its approval. In an interview with CNBC International, CEO Vlad Tenev acknowledged the tokens aren’t technically equity shares, but said that misses the broader point.

JPMorgan announces plans to charge for access to customer bank data

“What’s important is that retail customers have an opportunity to get exposure to this asset,” he said, pointing to the disruptive nature of AI and the historically limited access to pre-IPO companies.

“It is true that these are not technically equity,” Tenev added, noting that institutional investors often gain similar exposure through structured financial instruments.

The Bank of Lithuania — Robinhood’s lead regulator in the EU — told CNBC on Monday that it is “awaiting clarifications” following OpenAI’s statement.

“Only after receiving and evaluating this information will we be able to assess the legality and compliance of these specific instruments,” a spokesperson said, adding that information for investors must be “clear, fair, and non-misleading.”

Tenev responded that Robinhood is “happy to continue to answer questions from our regulators,” and said the company built its tokenized stock program to withstand scrutiny.

“Since this is a new thing, regulators are going to want to look at it,” he said. “And we expect to be scrutinized as a large, innovative player in this space.”

SEC Chair Paul Atkins recently called the model “an innovation” on CNBC’s Squawk Box, offering some validation as Robinhood leans further into its synthetic equity strategy — even as legal clarity remains in flux across jurisdictions.

Despite the regulatory noise, many investors remain focused on Robinhood’s upside, and particularly the political tailwinds.

The company is positioning itself as a key beneficiary of Trump’s newly signed megabill, which includes $1,000 government-seeded investment accounts for newborns. Robinhood said it’s already prototyping an app for the ‘Trump Accounts‘ initiative.

WATCH: Watch CNBC’s full interview with Robinhood CEO Vlad Tenev

Watch CNBC's full interview with Robinhood CEO Vlad Tenev

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Hyundai and Kia are betting on lower-priced EVs to ride out tariffs

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Hyundai and Kia are betting on lower-priced EVs to ride out tariffs

Korean auto giants Hyundai and Kia think lower-priced EVs will help minimize the blow from the new US auto tariffs. Hyundai is set to unveil a new entry-level electric car soon, which will be sold alongside the Kia EV2. Will it be the IONIQ 2?

Hyundai and Kia shift to lower-priced EVs

Hyundai and Kia already offer some of the most affordable and efficient electric vehicles on the market, with models like the IONIQ 5 and EV6.

In Europe, Korea, Japan, and other overseas markets, Hyundai sells the Inster EV (sold as the Casper Electric in Korea), an electric city car. The Inster EV starts at about $27,000 (€23,900), but Hyundai will soon offer another lower-priced EV, similar to the upcoming Kia EV2.

The Inster EV is seeing strong initial demand in Europe and Japan. According to a local report (via Newsis), demand for the Casper Electric is so high that buyers are waiting over a year for delivery.

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Hyundai is doubling down with plans to introduce an even more affordable EV, rumored to be the IONIQ 2. Xavier Martinet, CEO of Hyundai Motor Europe, said during a recent interview that “The new electric vehicle will be unveiled in the next few months.”

Hyundai-Kia-lower-priced-EVs
Hyundai Casper Electric/ Inster EV models (Source: Hyundai)

The new EV is expected to be a compact SUV, which will likely resemble the upcoming Kia EV2. Kia will launch the EV2 in Europe and other global regions in 2026.

Hyundai is keeping most details under wraps, but the expected IONIQ 2 is likely to sit below the Kona Electric as a smaller city EV.

Hyundai-Kia-lower-priced-EVs
Kia Concept EV2 (Source: Kia)

More affordable electric cars are on the way

Although nothing is confirmed, it’s expected to be priced at around €30,000 ($35,000), or slightly less than the Kia EV3.

The Kia EV3 starts at €35,990 in Europe and £33,005 in the UK, or about $42,000. Through the first half of the year, Kia’s compact electric SUV is the UK’s most popular EV.

Hyundai-Kia-lower-priced-EVs
Kia EV3 (Source: Kia)

Like the Hyundai IONIQ models and Kia’s other electric vehicles, the EV3 is based on the E-GMP platform. It’s available with two battery packs: 58.3 kWh or 81.48 kWh, providing a WLTP range of up to 430 km (270 miles) and 599 km (375 miles), respectively.

Hyundai is expected to reveal the new EV at the IAA Mobility show in Munich in September. Meanwhile, Kia is working on a smaller electric car to sit below the EV2 that could start at under €25,000 ($30,000).

Hyundai-Kia-lower-priced-EVs
Kia unveils EV4 sedan and hatchback, PV5 electric van, and EV2 Concept at 2025 Kia EV Day (Source: Kia)

According to the report, Hyundai and Kia are doubling down on lower-priced EVs to balance potential losses from the new US auto tariffs.

Despite opening its new EV manufacturing plant in Georgia to boost local production, Hyundai is still expected to expand sales in other regions. An industry insider explained, “Considering the risk of US tariffs, Hyundai’s move to target the European market with small electric vehicles is a natural strategy.”

Hyundai-Kia-lower-priced-EVs
2025 Hyundai IONIQ 5 (Source: Hyundai)

Although Hyundai is expanding in other markets, it remains a leading EV brand in the US. The IONIQ 5 remains a top-selling EV with over 19,000 units sold through June.

After delivering the first IONIQ 9 models in May, Hyundai reported that over 1,000 models had been sold through the end of June, its three-row electric SUV.

While the $7,500 EV tax credit is still here, Hyundai is offering generous savings with leases for the 2025 IONIQ 5 starting as low as $179 per month. The three-row IONIQ 9 starts at just $419 per month. And Hyundai is even throwing in a free ChargePoint Home Flex Level 2 charger if you buy or lease either model.

Unfortunately, we likely won’t see the entry-level EV2 or IONIQ 2 in the US. However, Kia is set to launch its first electric sedan, the EV4, in early 2026.

Ready to take advantage of the savings while they are still here? You can use our links below to find deals on Hyundai and Kia EV models in your area.

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Blink Charging just threw a lifeline to EVBox Everon customers

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Blink Charging just threw a lifeline to EVBox Everon customers

As EVBox shuts down its Everon business across Europe and North America, EV charging provider Blink Charging is stepping up to offer support to customers caught in the transition.

EVBox’s software arm Everon recently announced it’s winding down operations alongside EVBox’s AC charger business. That’s left a lot of charging station hosts and drivers wondering what comes next. Now, EVBox Everon is pointing its customers toward Blink as a recommended alternative.

Blink says it’s ready to help, whether that means keeping existing chargers up and running or replacing aging gear with new Blink chargers.

“EVBox has played a significant role in the growth of EV charging infrastructure across the UK and Mainland Europe, and we recognize the trust hosts have placed in its solutions,” said Alex Calnan, Blink Charging’s managing director of Europe. “With the recent announcement of Everon’s withdrawal from the EV charging market, it’s natural to have questions about what this means for operations. At Blink, we want to assure Everon customers that we are here to help them navigate this transition.”

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Blink says it’s able to offer advice, replacements, and ongoing network management to make the changeover as smooth as possible.

Everon users who switch to Blink will get access to the Blink Network portal via the Blink Charging app. That opens up real-time insight into charger usage and lets hosts set pricing, manage users, and download performance reports.

“At Blink, our charging technology is future-ready,” added Calnan. “With advancements like vehicle-to-grid technology on the horizon, our chargers are built to support the future of electric vehicles and charging habits.”

The company says its chargers are in stock and ready to ship now for any Everon customers looking to make the jump.

In October 2024, France’s Engie announced it would liquidate the entire EVBox group, which it said posted total losses of €800 million since Engie took over in 2017. EVBox is closing its operations in the Netherlands, Germany, and the US.


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