Case Study: Making luxury hotels on Santorini comfortable and energy-efficient
Reading time: 4 Min
The Voreina Gallery Suites look out over the cliffs of the Greek volcanic island of Santorini as if from the auditorium of an ancient amphitheatre. The owner of this carefully designed boutique hotel, Lefteris Zorzos, already had 16 solar thermal panels with 40m² on top of his 13 luxury suites to make free use of the warm Mediterranean sun. However, he wondered why his boiler was burning oil even on a summer day.
Mr. Zorzos asked some heating specialists to propose improvements by which he could increase his share of solar energy usage, thus reducing operating costs and improving the green image of his hotel. Moreover, he did not want to compromise the level of comfort for his guests and maintain better control himself of how well the system was performing.
He soon found that most salesmen just wanted to sell him a new heat pump or a biomass boiler but did not identify the root problem – the hot water storage was undersized. As a result, Mr. Zorzos opted for a redesign of his two boiler rooms.
Redesigning the Boiler Rooms
Two new, strongly insulated cylinders were fitted to double the storage volume from 800l to 1,600l – one for domestic hot water and one of equal size for heating the swimming pools.
An XTDC differential controller was installed to manage the complete system holistically. The control system was connected to the Internet via SOREL Connect, to give Mr. Zorzos the ability to see the system status on his mobile phone in real time and get information about the achieved energy savings. With such a monitoring tool at hand, he would have detected the energy he had wasted for many years much sooner.
After some time, he concluded that his oil consumption was reduced by almost 45%. The investment would thus be amortized within 3 years. Mr. Zorzos was very satisfied. As a result, it did not take long before he contacted the same contractors again for the next project.
Follow-up Project for Building a Luxury Villa
Soon after, Mr. Zorzos planned to expand his hotel group by building a new luxury villa for his so-called Pyrgos Houses. This time, his goal was an integrated system for heating, cooling and domestic hot water from the beginning. It was supposed to provide highest comfort to spoil his guests, and still keep the energy bill low for the hotel.
In the end, the winning design included the following characteristics:
- Integrated wall heating in the bathrooms. With an 8mm pipe, the heat distribution was built into the wall to save space and reduce consumption
- Fan coils for heating and cooling with low consumption and particularly low noise level for use in hotels
- 8kW inverter heat pump for heating and cooling, and a 12kW heat pump for DHW and the swimming pools. All of this is controlled by an LHCC heating and cooling controller
- °CALEON Clima Smart Room Controllers to provide a neat user interface for the visitors to adjust the room temperatures, as well as remote control for the owner. Taking data such as humidity and temperature, it creates the most comfortable atmosphere, with the lowest possible consumption.
- 6m² solar thermal system for DHW with 2 high-efficiency flat-plate collectors with a 10-year warranty, and an LTDC solar controller.
- Fresh Water Station up to 150l/min for hygienic domestic hot water and legionella protection controlled by an MFWC controller
- Monitoring of the installation from a mobile application. In this way, the hotel owner could see the real energy savings from his new system. Moreover, given that he likes to live in Athens during wintertime, he can switch the system remotely and change between heating and cooling season anywhere anytime.
LHCC for Heating and Cooling | °CALEON Clima Room Controller | Monitoring the Solar System
The villa is now run by 100% renewable energy sources and, consequently, with very low operating costs. The green character of the villa adds to the appeal to its guests. Hotel guests even mention the climatization systems favourably in their Internet reviews. Moreover, based on the good system performance in the field, the system supplier and the installer have created themselves a blueprint to reuse in future installations.
About the Author
Leonidas Nikolopoulos is a mechanical engineer with a passion for green technology.
His company Lennik Agencies has represented SOREL in Greece since 2016.