Revincus Targets 10 MWh Daily Heat Recovery on AIDA Ships

By Elena Vasquez

Revincus estimates selected AIDA ships could yield about 10 megawatt-hours of usable thermal energy daily from wastewater, based on an initial assessment. The small startup from Weimar, Germany, won the AIDA Innovation Hub decarbonization category in Rostock on Sept. 16 and has begun an implementation study (a vessel design and feasibility assessment) with AIDA.

The 10 MWh figure is preliminary, not a measured fuel saving or verified emissions reduction. Co-founder and technical managing director Felix Drechsel said engines generally supply enough waste heat while underway, making recovery most useful in port. The announcement discloses no capital cost, energy saving, carbon impact or vessel payback.

What does this mean for travel sellers?

Nothing announced changes bookings, fares or travel-agent commissions, so distribution effects remain absent. For cruise sellers, lower fuel use could support operator margins and pricing if the retrofit proves economical.

For revincus, shipyards and cruise operators, fleet adoption would shape potential equipment revenue and cost savings; no market-share claim is supportable without contracts or operating data.

Drechsel developed the concept during a post-school placement in Finland at a company that designed and installed heat-pump systems, where he learned that efficiency depends on source temperature. He concluded that hot water in homes, pools and ships continually sends thermal energy into wastewater.

He later met Jeremias Polster while studying in Weimar, and they built heat exchangers to recover that waste heat. Revincus has installed units in large residential buildings, housing estates, swimming pools and pharmaceutical plants; pool systems also recover heat from shower water and filter backwash (water used to clean filters). The vessel would be a new customer category for the supplier.

How does ship wastewater become usable heat?

Drechsel likens a cruise ship to a small floating town because it produces nearly every wastewater type found in one. Ships collect greywater (wastewater separated from blackwater), and treated greywater retains heat.

Revincus plans to install a wastewater heat exchanger and heat pump (a device that lifts low-grade heat to a usable temperature) after the greywater treatment plant, then feed recovered heat into the ship's heating system. The initial application would preheat fresh drinking water before bringing it to hot-water temperature.

Drechsel said: “What I find particularly interesting is that we do not need to tap into a new energy source or use additional fuel, but rather utilize heat that is already available on board and which, until now, has been released into the sea without being used.”

The claim defines the proposition as recovering heat already aboard, not adding a power source. It leaves how much engine heat the system displaces while in port, and the fuel-saving share of 10 MWh, unquantified.

The technical obstacle is contamination: solids and fats block ordinary plate or shell-and-tube units, which route fluids through plates or internal pipes, or quickly reduce their efficiency. Revincus uses a different heat-transfer arrangement.

• Heat transfer: A larger tank holds wastewater around stainless-steel plates. Cooler water flows inside the plates, absorbing heat from the surrounding wastewater; a heat pump then lifts that heat to a useful temperature.
• Cleaning: A movable cleaning comb with brushes travels between the plates and scrapes off deposits. Once the tank empties, nozzles spray the plates; the cycle runs automatically without manual scrubbing.
• Residue: Treated greywater contains fewer fats, but biofilms (microbial films) still build over time and act as insulation, so Drechsel said the system still requires cleaning.

Can revincus install the system on an existing ship?

Revincus has visited one vessel in AIDA's fleet to inspect technical and spatial conditions, and Drechsel said the visit went well. He considers the connection to the existing greywater treatment system technically feasible, but the announcement discloses no completed sea trial.

Space remains the principal retrofit (equipment added to an existing vessel) constraint because AIDA's technical compartments are fully planned and occupied. The team is sizing components around actual wastewater volumes, checking economics, and addressing approvals, certification and ship safety requirements.

No contract value, installation price, fuel-saving percentage or emissions calculation has been disclosed. Any margin benefit for travel sellers would depend on an operating vessel demonstrating lower energy use without compromising space, wastewater handling or safety.

Can one ship lead to fleetwide adoption?

Before working with AIDA, revincus tried to contact shipyards to raise awareness of wastewater heat recovery, but its small size and relative obscurity made that difficult. The award and resulting project opened a route the company had long sought.

Drechsel said: “We are, in fact, already well into the implementation study.” No vessel order, fleetwide agreement or contracted cruise-sector revenue has been disclosed.

The five-year goal is to commission (install and begin operating) the first system on an AIDA ship, then persuade AIDA, Carnival and other cruise lines to retrofit their fleets and specify heat recovery for new-construction vessels.

Success could expand revincus beyond buildings, pools and pharmaceutical users into a larger marine-equipment market. No vessel pipeline or order book is disclosed.

The next verifiable test is a certified AIDA installation that documents recovered energy against the 10 MWh daily estimate, along with downtime, cleaning requirements and installed cost. Until those figures exist, the project remains a maritime-efficiency trial with potential operating-cost relevance for cruise sellers, not a demonstrated change in cruise economics or distribution.