Wärtsilä explains that Greece’s energy needs differ greatly, primarily due to seasonal changes. During summer, the nation of 10.7 million people nearly triples in population as tourists flock to the diverse islands of the country. Also, there is a difference in the Greek mainland or the Greek islands.
Wärtsilä claims that is PLEXOS power system modelling can help tide over such uncertainties by designing an optimal solution, whereby the demand of each hour of every year is met in the most cost-efficient manner.
The system has been placed on Greece’s third largest island, Lesvos. The modelling has shown that 100% decarbonisation on the island is possible as early as 2025.
Tord Johnsson, General Manager Strategy and Growth Projects, Europe & Africa, at Wärtsilä Energy commented that
Lesvos island is a typical Greek island in regard to its power profile today.
PLEXOS power system modelling shows five different scenarios, explaining what happens when nothing changes to what happens when optimal changes are made.
- Business continues to operate as normal: After 2024, light fuel oil (LFO) replaces heavy fuel oil (HFO) while maintaining the existing installed capacity on the island. There are no new builds, and nothing is retired.
- Free optimization: After 2024, LFO replaces HFO and PLEXOS is free to optimize the system without constraint.
- 100% renewable energy sources: After 2024, LFO replaces HFO. Then, each year until 2030, the proportion of renewable energy sources used for electricity generation is increased, thereby reaching the 100% renewable energy target.
- 100% decarbonization: After 2024, biodiesel replaces HFO and LFO. Fuel conversion for existing engines and open-cycle gas turbines on the island amounts to half of the new-build costs.
- 100% renewable energy is achieved with Power-to-Fuel:
After 2024, synthetic fuel becomes the only fuel available and islands should build Power-to-Fuel converters that produce the synthetic fuels.
Yet, it is noted that the model also demonstrates limitations that when relying only on the intermittent renewable energy sources of wind, solar and capacity provided by batteries will help islands achieve only 80% decarbonization. Additional limitations include geographical constraints. Using wind turbines to generate 100% of power for islands is not only expensive, but most don’t have the space. Moreover, many people perceive wind turbines to be obstructions to the natural beauty of the islands.
Wärtsilä concludes that since transforming Greece’s touristic hotspots into wind turbine farms is far from ideal, compromise is necessary, particularly on days when there isn’t wind or sun to create power. Instead, battery storage systems and thermal capacity fill the gap.