On November 13, 2026, four companies, NTT Docomo Business, NTT Green & Food, IMT Engineering, and Hibiya Engineering, announced a joint demonstration project to use data center waste heat to warm water for land-based aquaculture. Using a data center in the Tokyo suburbs, the companies will evaluate methods of recovering waste heat in fiscal 2026. In fiscal 2027, they plan to use the recovered heat to warm rearing water and farm whiteleg shrimp (Penaeus vannamei). The demonstration period is scheduled to run through March 2028. The project is not simply about raising shrimp with waste heat. It aims to establish a design method that identifies the temperature and amount of waste heat, which differ from one data center to another, and calculates the aquaculture facility size suited to each set of conditions.
Using low-temperature data center waste heat as a heat source for aquaculture
As generative AI spreads, data center power consumption is rising, and making effective use of the heat released by cooling equipment has become an issue. Data center waste heat is relatively low in temperature, which limits its uses. Land-based aquaculture, meanwhile, requires keeping water at a temperature suited to the fish and shellfish, and continuous heating consumes energy. If the right temperature conditions are met, data center waste heat could potentially be used to warm rearing water.
The Tokyo Metropolitan Government announced on October 6, 2026 that this demonstration was among three projects selected. On the following day, NTT Green & Food announced the collaboration and demonstration plan, saying work would begin in October. Then, in the joint announcement by the four companies on November 13, the specific schedule for each fiscal year was made clear.
In fiscal 2026, the companies will recover waste heat from the data center's cooling equipment, measure the amount and temperature of heat that can be extracted, and evaluate suitable recovery methods. In fiscal 2027, based on those results, they will use the recovered heat to warm rearing water and farm whiteleg shrimp. Through actual rearing, they will confirm whether water temperature can be maintained stably and whether energy consumption can be reduced compared with conventional heating methods. They will also verify how waste heat recovery affects data center operations.
Calculating suitable facility size from waste heat temperature and amount
Even when a data center generates waste heat, that heat alone cannot necessarily sustain aquaculture at a given scale. To determine facility size, it is necessary to confirm not only the amount and temperature of heat that can be recovered, but also whether rearing water temperature can be maintained when the heat supply fluctuates. The temperature change that occurs between recovering the heat and delivering it to the aquaculture equipment must also be taken into account.
In its October announcement, NTT Green & Food explained that the amount of waste heat generated varies with the season and the data center's operating status. Because cooling methods and equipment operation also differ from site to site, results obtained at one facility cannot necessarily be applied as they are to another data center. The four companies will therefore use actual operating data to create an index linking the temperature and amount of recoverable heat to aquaculture facility size. Their ultimate goal is to establish a design method that can be used at data centers with different cooling methods and waste heat conditions.
Based on the four companies' announcement and the Tokyo Metropolitan Government's selection materials, the main items to be verified and what can be judged from each result are summarized below.
| Item to be verified in the demonstration | What the result will help determine |
|---|---|
| Amount and temperature of waste heat recovered in fiscal 2026, and recovery methods | Conditions of heat that can be extracted from the data center and used |
| Temperature change before heat is supplied to aquaculture equipment | Temperature conditions of heat that can be used to warm rearing water |
| Variation in waste heat with season and operating status, and water temperature maintenance performance | Conditions under which water temperature can be maintained despite heat supply fluctuations, and suitable aquaculture facility size |
| Shrimp rearing in fiscal 2027, heating energy reduction, and impact on data center operations | Whether stable rearing and energy savings can both be achieved, and whether data center operations are unaffected |
| Production cost reduction and commercial viability | Profitability, as a basis for deciding on expansion to other sites |
All items are demonstration plans as of the October and November 2026 announcements, not verified results.
The key point is that knowing how much heat can be recovered is a separate matter from being able to sustain stable aquaculture with that heat. It will be necessary to confirm whether appropriate water temperature can be maintained even when the waste heat supply fluctuates, and then evaluate the heating energy reduction and commercial viability.
In the demonstration, each of the four companies will handle its own area of expertise. NTT Docomo Business will provide the demonstration site and evaluate the effects of waste heat recovery on data center equipment. Hibiya Engineering will design and build the waste heat recovery and supply equipment, while IMT Engineering will design the aquaculture system and operate the rearing facility. NTT Green & Food will handle sensing and monitoring of the rearing environment and evaluate the production cost reduction and commercial viability.
Balancing heating energy savings and commercial viability
Even if data center waste heat reduces heating energy, that alone does not necessarily improve the profitability of an aquaculture business. Capital investment and operating costs are also required to recover the waste heat and supply it to the aquaculture equipment. The four companies will take such costs into account as they verify production cost reductions and commercial viability, aiming to build a business model that can be rolled out to a variety of data centers.
At this point, figures such as the temperature and amount of recoverable waste heat, the specific size of the aquaculture facility, the rate of heating energy reduction, and the capital investment have not been disclosed. Whether waste heat recovery affects the data center's cooling performance or operations will also be confirmed in the fiscal 2027 demonstration. For these reasons, the energy-saving effects and economic benefits cannot be quantitatively assessed from this announcement alone.
The focus going forward is under what waste heat conditions rearing water temperature can be kept stable, and how much heating energy can be reduced. It will also be important to clarify the facility size and production cost suited to those conditions, and to establish a design method applicable to sites with different cooling methods and waste heat conditions. If the demonstration makes these conditions concrete, it will provide material for judging the feasibility of using unused data center heat for land-based aquaculture.