A long-shuttered US nuclear reactor has moved closer to a planned 2027 restart after securing two important regulatory boosts from federal agencies.

The US Federal Energy Regulatory Commission has approved Constellation’s request to transfer 760 MW of capacity interconnection rights from another Pennsylvania power plant to the former Three Mile Island unit 1.

The reactor, now called the Crane Clean Energy Center, is being prepared for a return to service in 2027.

Separately, the US Nuclear Regulatory Commission has issued for public comment its draft finding that restarting operations at the site would have no significant environmental impact.

Constellation announced in 2024 that it planned to restart the pressurized water reactor, which was shut down in 2019.

The company later filed an interconnection request with regional grid operator PJM to allow Crane to add 835 MW of emissions-free electricity to the grid.

The rights that could support return

To help support the 2027 restart schedule, Constellation filed a waiver request with FERC on March 31. The request sought permission to transfer capacity rights from Eddystone, a six-unit, dual-fuelled plant in Pennsylvania.

Two 380 MW units at Eddystone, known as Eddystone 3 and 4, had been scheduled to close last year.

However, they have remained online beyond their planned retirement date to support grid reliability under emergency orders issued by US Energy Secretary Chris Wright.

FERC has now granted the waiver, allowing Constellation to remove the Eddystone units from Capacity Resource status and make their capacity interconnection rights available for transfer. The decision was issued by FERC on June 1.

NRC opens restart review for public comment

The second regulatory boost came from the NRC. On June 8, the agency issued a draft environmental assessment and draft finding of no significant impact, or FONSI, for public comment.

The review evaluated the reasonably foreseeable environmental effects of allowing power operations to resume at Three Mile Island unit 1. At the time of its closure in 2019, the reactor had a renewed operating license valid until 2034.

Constellation has asked the NRC to approve one exemption request and three license amendment requests to support the resumption of power operations through the previous license expiration date.

The company has also said it plans to seek an extension that would allow Crane Clean Energy Center to operate beyond that, to 2054.

The NRC’s draft assessment concluded that restarting operations would not require a full environmental impact statement.

The Commission said in a Federal Register notice that “the NRC staff has made the preliminary determination that the proposed actions will not have a significant effect on the quality of the human environment. Therefore, the NRC staff has made the preliminary determination that it will not prepare an environmental impact statement (EIS) for the proposed actions and that a FONSI is warranted.”

The NRC will make its final decision after reviewing comments received during the 30-day public comment period, which runs until July 8.

A Finnish deep-tech energy startup is moving to industrialize a renewable supercapacitor made from waste wood and agro residues, offering a fast-response power storage layer for grids and industrial operations.

Granarium Technologies, which originated from VTT, is developing a patented nanocellulose-based energy storage technology that upcycles waste materials into 100% renewable supercapacitors.

The technology uses a nanocellulose-based material platform that binds biocarbon structures for power storage, creating systems the company says are safe, scalable, and locally producible.

The system is designed to complement batteries, not replace them. It targets short-duration power needs such as grid balancing, frequency response, peak load management, distributed power generation, and industrial power quality.

Fast-response storage for unstable grids

The shift to renewable energy and electrification is increasing pressure on power networks, especially as grid volatility rises across Europe and EU requirements around grid codes and resilience frameworks tighten.

Granarium’s technology aims to provide a fast-response layer within energy systems, helping grids and industrial facilities respond quickly to fluctuations in power supply and demand.

“A key structural shift is that storage is no longer just `backup power’ – it is becoming core grid infrastructure. Granarium is the perfect addition to our portfolio because the company is solving a massive global challenge in a safe and scalable way,” said Jana Budkovskaja, Partner at BSV Ventures.

“We were also impressed with the company’s technology and experience, as well as the capacity to use local raw materials to make the production process sustainable and inexpensive,” he said.

According to the company, the technology can enable up to 80% lower production capital expenditure compared with large-scale battery manufacturing investments.

Built from local renewable carbon

Granarium’s approach is based on renewable carbon sources instead of finite critical raw materials. By using waste wood and agro residues, the company says its devices can be produced using locally sourced materials, reducing reliance on complex logistics chains.

The underlying technology and intellectual property have been transferred from VTT to the newly established company, giving Granarium a route to turn advanced bio-based material research into commercial energy storage systems.

“Granarium demonstrates how successful technology transfer can turn advanced bio-based materials into real industrial solutions for secure and resilient energy storage,” said Atte Virtanen, Vice President, Advanced bio-based materials at VTT.

Pilots planned within six months

Granarium has secured pilot customers and key value chain partners and is preparing to launch its first pilots within six months.

The initial deployments will focus on process industries and continuously running production operations, where power quality and stability are critical.

Initial commercial production will begin at a small industrial scale, with capacity to deliver up to 50 units per year.

The company plans to use this phase as the basis for rapid scale-up through industrial partnerships and international market expansion.

“We are not just improving existing solutions but redefining how power storage can be built and utilized,” said Otto-Ville Kaukoniemi, CTO at Granarium.

“Compared to lithium-based energy storage devices that utilise finite resources, our devices are far more environmentally sustainable as they derive from local and self-sufficient renewable carbon sources, and lower in cost to produce compared to battery gigafactory investments,” he added.

Some science experiments last a few minutes. Some take years. And then there is the Pitch Drop Experiment, which has been running for nearly a century and is still not finished.

The Pitch Drop Experiment, housed at the University of Queensland in Australia, is widely known as the world’s longest-running laboratory experiment.

A liquid that looks solid

The material at the center of the experiment is called pitch. Pitch is a black, tar-like substance that was once commonly used for waterproofing boats.

At room temperature, it looks, and feels solid. You can hit it with a hammer and it may shatter like glass. But scientifically, pitch is not a true solid. It is an extremely viscous liquid, meaning it can flow — just very, very slowly.

To prove this, Parnell heated some pitch and poured it into a glass funnel. He then let it settle for several years.

In 1930, the stem of the funnel was cut, allowing the pitch to begin its slow journey downward. Since then, the experiment has consisted of waiting for drops of pitch to fall from the funnel into a beaker below.

Why one drop takes years

That is where the experiment becomes famous. Since it began, only nine drops have fallen. The ninth drop separated in April 2014 during an operation to replace the beaker beneath it. The tenth drop is still forming.

The reason it takes so long is viscosity. Viscosity is a measure of how resistant a fluid is to flowing. Water has low viscosity, so it pours quickly. Honey has higher viscosity, so it flows more slowly. Pitch is on another level entirely.

The University of Queensland describes pitch as the world’s thickest known fluid, and Guinness World Records notes that the experiment has shown pitch to be about 100 billion times more viscous than water.

This is why the Pitch Drop Experiment is so useful as a teaching tool. It challenges our everyday idea of what solids and liquids are. We usually judge materials based on what we can see over a short time. If something does not move in front of us, we call it solid.

But science often works on timescales far beyond human patience. A mountain may seem permanent, but it can erode.

Glass may look rigid, but materials can behave differently under different conditions. Pitch shows that some substances can appear solid in daily life while still flowing over long periods.

A century-long lesson in patience

The experiment is also famous because of its strange history of near-misses. For decades, no one actually saw a drop fall in person. Drops fell at inconvenient moments, or cameras failed to capture them.

The eighth drop fell in 2000, and the ninth separated in 2014. Today, the experiment can be watched online, turning one of the slowest events in science into a kind of global waiting game.

What makes the experiment remarkable is not technological complexity. It is actually very simple: pitch, a funnel, a beaker, and time. But that simplicity is exactly why it works.

It makes an invisible idea visible. It turns viscosity from a textbook term into something you can understand with one image: a drop that takes years to fall.

The Pitch Drop Experiment is not about speed, spectacle, or instant results. It is a reminder that nature does not always move at the pace humans expect. Some truths reveal themselves only when someone is patient enough to keep watching.

Nearly 100 years after it began, the experiment continues. And somewhere inside that glass funnel, the next drop is slowly making its way down.

Buildings are often judged by height, beauty, engineering complexity, or cultural importance. But there is another way to measure ambition: cost.

The world’s most expensive buildings are not just oversized construction projects. They are statements of religion, tourism, technology, sport, luxury, and national identity.

Some were built to host millions of pilgrims. Others were designed to redefine entertainment, corporate campuses, or stadium architecture.

From Mecca to Singapore, California, and Macau, these seven buildings show how far architecture can go when budgets stretch into billions of dollars.

1. Al-Masjid al-Haram, Saudi Arabia

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Price: $100 billion

The most expensive building in the world is not a skyscraper or a casino. It is Al-Masjid al-Haram in Mecca, Saudi Arabia.

The mosque has been expanded repeatedly over centuries, but its modern expansion projects have turned it into one of the largest religious complexes ever built.

Today, it covers around 356,800 square meters and can hold up to 820,000 worshippers. Ongoing expansion work aims to increase that area to about 456,000 square meters and raise capacity to around 1.2 million people.

2. Abraj Al Bait Towers, Saudi Arabia

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Price: $19.5 billion

Standing next to the Grand Mosque, the Abraj Al Bait Towers form one of the most recognizable skylines in Mecca.

The complex is best known for the Mecca Royal Clock Tower Hotel, a central skyscraper that rises over 1968 feet (600 meters). Its giant clock faces are among the largest in the world, each measuring around 141 feet (43 meters) in diameter and lit by more than two million LEDs.

But the project is not just about height or spectacle. It was built to support the huge number of pilgrims who travel to Mecca every year for Hajj and Umrah.

The hotel complex can accommodate more than 30,000 people and includes over one million square meters of floor space.

3. Marina Bay Sands, Singapore

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Price: $7.8 billion

Marina Bay Sands is one of those buildings that became a global icon almost instantly.

Located in Singapore, the complex includes a hotel, casino, shopping mall, exhibition center, theaters, restaurants, bars, and the ArtScience Museum. But its most famous feature is the massive rooftop SkyPark that stretches across three 55-story towers.

The roof garden sits nearly 623 feet (190 meters) above the ground and includes one of the world’s most famous infinity pools.

Designed by architect Moshe Safdie, the structure was reportedly inspired by stacked playing cards, which explains its dramatic, almost impossible-looking form.

4. SoFi Stadium, United States

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Price: $5.5 billion

SoFi Stadium in Inglewood, California, is the most expensive stadium ever built.

Opened in 2020, it is home to the Los Angeles Rams and Los Angeles Chargers. The stadium can seat more than 70,000 people and can be expanded to over 100,000 for major events.

But the cost is not just about seating capacity. SoFi Stadium features a huge translucent roof, a 360-degree video board, premium hospitality spaces, and a futuristic design built for NFL games, concerts, Super Bowls, and other global events.

5. Apple Park, United States

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Price: $5 billion

Apple Park in Cupertino, California, is one of the most famous corporate headquarters in the world.

Often called “the spaceship,” its ring-shaped main building measures around 1,509 feet (460 meters) in diameter and contains about 260,000 square meters of office space. It was designed to reflect Apple’s obsession with simplicity, precision, and product-like architecture.

The building uses large curved glass panels, open workspaces, landscaped surroundings, and energy-efficient design. The campus is home to more than 12,000 employees and is surrounded by thousands of trees.

6. Resorts World Sentosa, Singapore

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Price: $4.9 billion

Singapore appears again on the list with Resorts World Sentosa, a massive integrated resort on Sentosa Island.

The complex includes luxury hotels, restaurants, event spaces, shopping areas, two casinos, a water park, Universal Studios Singapore, and the S.E.A. Aquarium, which houses more than 100,000 marine animals.

Unlike a single tower or stadium, Resorts World Sentosa is more like an entire entertainment district packed into one destination. It was designed to attract tourists, families, business travelers, and casino visitors at the same time.

7. Wynn Palace, Macau

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Price: $4.2 billion

Wynn Palace in Macau completes the top seven with an estimated construction cost of $4.2 billion.

Located in the Cotai district, often compared to the Las Vegas Strip, Wynn Palace is a luxury resort built around high-end hospitality, gaming, retail, and entertainment.

The complex includes more than 1,700 rooms and suites, a casino, luxury boutiques, restaurants, a spa, and an artificial lake.

One of its standout attractions is a performance lake with fountains, light, and music, along with a cable car system that adds to the theatrical experience.

More than buildings

The seven most expensive buildings in the world are very different from one another. But they all have one thing in common: they were built to do more than occupy space.

They were built to create identity, attract people, support economies, and project ambition at an enormous scale. Their price tags are huge, but so are the purposes behind them.

In that sense, the most expensive buildings in the world are not just examples of lavish spending. They are monuments to what societies, companies, and cities choose to value most.