The construction of the green energy plants corresponds to a modification of the Food & Energy Training Center developed by Sunfarming, which is already operated at universities in Argentina, the Dominican Republic, the Bahamas and Turkey. The raised PV tables with a height of 2.3 m by 3.3 m are covered with bifacial double glass PV modules and the space in between is closed with a trapezoidal light band. Protection from direct sunlight and heavy rain offers the possibility of cultivating plants in arid areas and reducing water requirements.
In the Sunfarming Food & Energy lounge at Villa KaliMeera, a water-saving drip hose system is being laid to irrigate tomatoes, cucumbers and other local plants, the fruits of which are available to hotel guests as a fresh snack to pick themselves.
Climate and resource neutral travel
The calculated annual energy yield is around 16,500 kilowatt hours, one third of which can be purchased directly and two thirds can be used indirectly via a net metering billing system.
The tour operator ReNatour from Nuremberg designs the trips offered as climate and resource neutral as possible and the CO2 emissions caused by the journey can also be neutralized by the guests in cooperation with atmosfair gGmbH. The non-profit climate protection organization with a focus on "travel" supports the implementation of projects with donations that effectively reduce the emission of climate-damaging greenhouse gas emissions and promote the long-term retention of carbon dioxide - including this SUNfarming project in Corfu.
Gigantic virtual energy storage system
What the locations were still missing in order to become more climate-neutral is the electrical energy supply through renewable energies, according to Aias. Since the inadequate use of renewable energies in Greece makes it virtually impossible to purchase green electricity from the grid, the only alternative is to produce on-site solar energy with photovoltaic systems. Thanks to the cooperation between SUNfarming and atmosfair, this goal has now been achieved and two PV systems with a total capacity of 25 kilowatts have been installed, which from now on take care of 100% of the electrical energy supply for the hotels.
With the help of the new Greek net metering system, the energy that is not directly consumed is fed into the public power grid, registered by the network operator and drawn back from the grid as an equivalent at a later point in time as required. In this way, the seasonal operation can mathematically fall back on year-round sustainably generated energy. With this concept, the public grid functions as a gigantic virtual energy storage system and has the advantage over stationary PV storage systems of unlimited storage capacity and duration as well as the avoidance of additional investments. The fee incurred per kilowatt hour removed is a few cents and is below the specific costs per kilowatt hour stored by market-leading lithium-ion storage systems.
In this way, the existing solar potential, which in Greece is up to 1500 kilowatt hours per kilowatt - up to 150% of the German level - can be used particularly effectively and sensibly. (mfo)
