As knowledge heart operators face mounting vitality calls for and sustainability challenges, MIT researchers have recognized a promising, potential answer: changing outdated coal energy vegetation into thermal vitality storage services to energy knowledge facilities.
The state of affairs would breathe new life into closed or retiring coal-fired energy vegetation and permit operators to make use of their present infrastructure, grid connections, and land to retailer and supply renewable vitality to knowledge facilities, mentioned Yifu Ding, a post-doctoral analysis affiliate for the MIT Power Initiative and lead writer of a 2024 report on the topic.
The truth is, one vitality startup, Massachusetts-based Malta, Inc., is working to show the idea into actuality with its vitality storage expertise.
When vitality from photo voltaic and wind farms is considerable, Malta’s answer shops the renewable vitality as warmth in molten salt thermal storage methods. Then, when electrical energy is required, the saved thermal vitality is transformed again to electrical energy to produce vitality to knowledge facilities, defined Kevin Stone, Malta’s vp of engineering.
The result’s knowledge facilities that may use renewable vitality across the clock, even when the wind isn’t blowing or at night time when the solar isn’t shining.
“This can be a manner for knowledge facilities to make use of extra of their electrical energy as renewable electrical energy when it isn’t instantly obtainable,” Stone mentioned in an interview with DCN.
Analysis suggests expired coal services provide a number of repurposing alternatives past thermal vitality storage, together with websites for nuclear reactors and knowledge heart developments. Picture: Alamy.
Rolling Coal: What to Do With Shuttered Coal Energy Crops?
The coal business has continued its decline over the previous decade, and growing older coal energy vegetation proceed to close down as a consequence of environmental rules and competitors from extra reasonably priced options like pure gasoline energy vegetation and renewables like wind and photo voltaic.
In line with Ding’s research paper (PDF), ‘Repurposing Coal Energy Crops into Thermal Power Storage for Supporting Zero-carbon Information Facilities,’ expired coal services may be repurposed for not solely thermal vitality storage but additionally to accommodate nuclear reactors and even knowledge facilities.
Another choice is changing the outdated energy vegetation from coal to pure gasoline, which is cheaper and produces fewer carbon emissions. The truth is, the Homer Metropolis Producing Station, beforehand the most important coal-burning energy plant in Pennsylvania, will likely be remodeled right into a main pure gas-powered knowledge heart campus delivering as much as 4.5 GW of energy, its builders introduced in April.
In a bid to bolster the coal business, President Donald Trump recently signed executive orders that enable older coal vegetation scheduled for closure to stay open to satisfy the rising energy wants of AI and knowledge facilities.
Nevertheless, vitality market consultants predict that any coal business resurgence will probably be fleeting as a result of pure gasoline is cheaper and the renewable vitality market continues to broaden, in accordance with published reports.
Pennsylvania’s former largest coal plant, Homer Metropolis Producing Station, is being transformed right into a pure gas-powered knowledge heart campus with 4.5 GW capability. Picture: Homer Metropolis Redevelopment.
The Case for Retrofitting Coal Energy Crops
MIT Power Initiative’s Ding mentioned repurposing coal energy vegetation into thermal vitality storage presents a novel alternative for his or her house owners to revitalize their companies. It additionally supplies a ready-made atmosphere to accommodate knowledge facilities.
“Some coal vegetation are about to retire as a consequence of age,” she advised DCN. “There may be nice potential to accommodate knowledge facilities, and there’s potential to transform them to thermal vitality storage to reuse present grid interconnection and cooling infrastructure.”
As a substitute of utilizing a boiler to burn coal, coal energy plant house owners would change their boilers with molten salt vitality storage methods, she mentioned. Molten salt is a medium that may retailer warmth at excessive temperatures. When electrical energy is required, they’ll reuse their steam generators to show the warmth again into electrical energy, she mentioned.
That’s precisely how Malta’s expertise works. The startup, which spun off from Google’s X analysis division in 2018, has developed long-duration vitality storage expertise that may retailer warmth for eight hours to a number of days, in comparison with battery expertise that sometimes shops electrical energy for 4 to 6 hours.
Malta’s Molten Thermal Storage Answer
In an interview with DCN, Malta CEO Phil Delleville mentioned the corporate’s expertise has many functions, together with integration into coal and pure gasoline energy vegetation, district heating and cooling methods, and standalone functions, equivalent to geothermal vegetation.
Coal energy vegetation may be retrofitted with Malta’s expertise in numerous configurations, he mentioned. For instance, coal plant house owners can construct photo voltaic or wind farms on-site and hook up with Malta expertise. They’ll additionally set up a knowledge heart on the coal plant and use renewable vitality instantly with out connecting to the grid.
Alternatively, they’ll get electrical energy instantly from the grid. To get renewable vitality, they’ll prepare energy buy agreements (PPAs) with photo voltaic and wind farms. And if a knowledge heart is off-site, they’ll use the grid connection to export the facility to the info heart by PPAs, Stone mentioned.
“In a typical use case, we’re in a spot with quite a lot of solar energy through the center of the day. I take advantage of that to cost my system, and when the solar goes down, and I lose my solar energy, I begin up our system,” Stone mentioned. “Now I’m releasing vitality (from the thermal storage tanks) all through the night time, after which the following morning, I’ve used up all my storage, and we begin to cost once more when the solar comes up.”
Malta’s expertise, referred to as the Steam Power Administration and Storage (SEMS) answer, consists of three predominant elements: a warmth pump that converts electrical energy into thermal vitality, molten salt storage tanks that retailer the warmth, and steam generators that convert the saved warmth again into electrical energy when electrical energy is required, he mentioned.
The system contains software program: a complicated management system to run the plant, which features a digital twin and a grid optimization software program layer that analyzes costs for renewable vitality, the forecast for solar and wind and makes suggestions on when to retailer vitality within the tanks, Stone mentioned.
The startup’s SEMS expertise can combine with a coal energy plant’s present gear, equivalent to steam generators, piping and condensers. Since they not must stockpile coal or use a coal boiler, that area can be utilized for molten salt storage tanks.
“They’ve loads of area for us to switch these coal piles with molten salt storage,” Stone mentioned.
As soon as commercially deployed, the expertise can help between 100 MW to over 500 MW of energy.
The truth is, Malta plans to construct a commercial-scale 14 MWe demonstration plant in Spain designed to ship dispatchable clear vitality to the nationwide energy grid. The corporate will start building by late 2025, and the plant is predicted to turn into operational by late 2027.
General, on this particular use case, Malta’s expertise would enable coal energy vegetation to transition to cleaner vitality manufacturing whereas benefiting from its present infrastructure, Stone mentioned. It might additionally protect jobs of their communities.
“They’ll proceed to make the most of their asset, proceed to make use of the staff from that area and proceed to get constructive financial advantages,” he mentioned.
Amid hovering energy calls for, the info heart business is quickly pivoting towards modern vitality options, exploring every thing from retrofitted coal vegetation to thermal storage applied sciences. Picture: Alamy / DCN.
Enterprise Case for Retrofitting Coal Crops: Does It Make Financial Sense?
At MIT, Ding and her co-authors examined 12 coal energy vegetation throughout the Electrical Reliability Council of Texas (ERCOT)’s grid, simulating situations with retrofitted coal vegetation utilizing renewable vitality and co-located knowledge facilities.
They concluded that retrofitting coal vegetation with molten salt storage for zero-carbon knowledge facilities would value considerably lower than utilizing lithium-ion batteries.
Nevertheless, whether or not coal plant operators pursue a retrofit with thermal vitality storage will depend on U.S. insurance policies. If knowledge facilities don’t wish to go zero carbon or usually are not required to take action, coal plant operators might pursue a distinct plan for his or her services, Ding mentioned.
One industrial actual property dealer well-versed in vitality initiatives mentioned retrofitting coal vegetation for thermal vitality storage has potential, however questions whether or not it’s their finest use.
Bryce Custer, a accomplice with industrial actual property agency Ohio River Hall, has overseen website choice for pure gasoline energy vegetation and renewable vitality initiatives. His shoppers in Ohio, Pennsylvania, and West Virginia embrace builders, property house owners, and knowledge heart operators.
Discussing the problems raised by the MIT analysis paper, Custer advised DCN: “Based mostly upon my expertise with coal energy vegetation and different massive locations with massive infrastructure, it would work. However is it cost-effective? Will somebody wish to buy energy from these thermal vitality storage models?”
He added: “On the finish of the day, by the point I generate my renewable vitality, retailer it, and construct all my services and put these items in, does it make financial sense? That’s going to be the true query.”
A few 12 months in the past, coal plant house owners bought off their services to firms specializing in environmental mitigation. These firms demolish and clear up the websites after which resell them, Custer mentioned. However within the ensuing 12 months, coal plant house owners have rethought their methods as a result of they realized they have been giving freely a key asset.
“They understand now that there’s important worth within the land and the infrastructure in place,” he mentioned.
Custer believes the long run is nuclear by using small modular reactors (SMRs). However whereas that expertise continues to be in its nascent phases, repurposing former coal vegetation, metal mills, and different massive services into pure gasoline energy vegetation is good as a result of the realm – Ohio, Pennsylvania, and West Virginia – is dwelling to one of many largest provides of pure gasoline within the nation.
Some retired coal energy vegetation within the area have already been transformed to pure gasoline energy vegetation – and extra conversions are at present beneath dialogue.
“Proper now, probably the most cost-effective answer to generate electrical energy goes to be pure gasoline,” the vitality skilled mentioned.
Custer leaned into the thought of utilizing retired services equivalent to outdated coal energy vegetation to provide, not retailer, energy, notably given the rising knowledge heart energy drawback. He mentioned there could also be conditions the place thermal storage may make sense, however it could be extra of an outlier than a major choice.
“It’s an answer, little doubt,” Custer mentioned, referring to thermal storage. “I might quite be utilizing services to generate massive quantities of energy – be it renewables, SMRs or pure gasoline – than to make use of it to retailer vitality.”
Subsequent-Gen Power Expertise: An Operator’s Perspective
One knowledge heart operator mentioned repurposing coal vegetation with thermal vitality storage has benefit.
Rahul Mewawalla, CEO of the Mawson Infrastructure Group, mentioned the business wants extra modern considering relating to growing new sources of vitality whereas repurposing present infrastructure.
Mawson, based mostly in Midland, Pennsylvania, supplies digital infrastructure for AI, high-performance computing and digital belongings and operates three knowledge facilities within the U.S.
At a macro degree, Mewawalla mentioned he’s typically supportive of the MIT paper as a result of constructing a brand new vitality storage facility, from buying the land and putting in infrastructure to getting permits, may simply take three to seven years.
Repurposing coal energy vegetation with vitality storage can speed up the power to offer energy for knowledge heart operations, he mentioned.
“We’re supportive of repurposing present infrastructure to satisfy the vitality wants of tomorrow,” he advised DCN. “If you consider the greenfield vs. brownfield method, once you repurpose present infrastructure, you’re in a position to not solely save time, however you additionally save on capital expenditures.”
Nevertheless, on the vitality storage entrance, his firm has a long-term perception in battery vitality storage methods. For backup energy, a battery vitality storage system can reply to the grid in milliseconds, guaranteeing 24/7 redundancy, he mentioned.
Would the corporate use retrofitted coal vegetation with thermal vitality storage? It relies upon, Mewawalla mentioned.
“It would rely from market to market and facility to facility,” he mentioned. “Not all coal vegetation are the identical. Every of them is constructed otherwise in numerous markets. The overall method, which is a chance to repurpose these services with thermal vitality storage methods and use the present infrastructure, we’re typically supportive of.”
