Hotel resort in the Atlantic Ocean
Hot water on the Cape Verde islands
For a newly renovated hotel complex, two AC•THOR 9s prepare the hot water and use the surplus electricity from the photovoltaic system.

Facts
Planner: | meierelektro ag |
Type of building: | Renovated hotel complex |
Construction year and number of square meters: | Renovated in 2021, the hotel complex has 28 double rooms |
Photovoltaic output, orientation: | Photovoltaic system with 70 kWp, 10° inclination |
Heat storage size: | 2 electric hot water boilers with 2,000 liters each |
Used my-PV product + benefit: | 2 x AC•THOR 9s, for hot water preparation |
System control by/with?: | Solar Manager |
Customer declaration
How did you come upon my-PV?
The Swiss company "meierelektro ag" had already carried out a number of optimizations with Solar Manager and the AC•THOR 9s – but so far only in Switzerland, where the company is based. Since the previous optimizations in combination with the solution from Solar Manager and my-PV worked perfectly, the solution was also ready to be tested on the Cape Verde islands in the Atlantic.
The idea was that if the solution works in Switzerland, then it should be just as convincing in operation in the much sunnier location in the West of Africa. The even better location with significantly more hours of sunshine and almost balanced solar radiation all year round, including the angle of incidence of the sun, are absolutely perfect conditions for using the power of the sun also for the heating area.
Obstacles/peculiarities regarding the set-up?
Since the project was not implemented in Europe, with the usually well-timed logistics system, the island location of Cape Verde represented a particular challenge. In addition, there was also the distance from home that the Swiss company had to overcome – at least during the commissioning and implementation phase. Now in operation, the distance and the location are no longer an obstacle - on the contrary: Thanks to the cloud solution from Solar Manager, as well as from my-PV, the settings for hot water temperature or a possible hot water backup can be configured from anywhere in the world. Distance is no longer an obstacle – even in times of rising travel costs – as it is guaranteed that the settings can also be changed remotely.
Brief explanation of the system - what should be mentioned?
The conditions on the Cape Verde islands are perfect: good solar yields throughout the year, high electricity prices and high water prices. This makes it even more worthwhile for hoteliers, but also for private individuals of the island republic, to produce their own photovoltaic electricity and to make the most out of it. In this case, the water treatment system is operated with the hotel's own photovoltaic electricity as a second priority in addition to the hotel consumers during the day. As a third prioritization, excess is then used for hot water preparation, i.e. to heat the hot water during the day. This is of particular importance, because of course, the hotel guests don't want to be in the cold shower in the evening. With a total of 28 double rooms, there is a high amount of hot water requirement by the hotel guests. For this reason, the hotel complex requires two electric hot water boilers, each with a capacity of 2,000 litres; these are only intelligently controlled by the two AC•THOR 9s and supplied with surplus electricity from the photovoltaic system.
Even if this is not the case on many days: On days with too little photovoltaic yield, the AC•THOR 9s' tried-and-tested hot water backup can cover the required amount of energy with the regular public power grid and thus ensure that hotel guests can enjoy a warm shower. This is especially necessary in the evenings, since hotel guests almost exclusively need to take a shower in the evenings, which means that a lot of hot water is needed within a short period of time.
Moreover, the hotel complex also plans to continue using photovoltaic electricity for air conditioning and charging stations for electric cars in the future.
The operators of the hotel complex are very satisfied and are considering a further expansion of the photovoltaic system and the heating areas in the coming years. It remains to be decided whether this implementation will also be realized in other hotel complexes.
The implementing company, the Swiss company meierelektro ag, is definitely convinced of the joint solution of Solar Manager and my-PV.
"The compatibility works well and - this was shown in this project - the remote maintenance or the possibility of remote setting from Switzerland is a cost-saving and very practical feature via the cloud. The AC•THOR 9s also works in a hotel complex in the West of Africa – even when the hotel complex is in full operation,” concludes the managing director of meierelektro ag.