Prosperity follows electricity, and one small island is taking steps to develop its economy and its power supply system by embracing the latest renewable energy storage solutions.
Roatan, a small island off the coast of Honduras in Central America, is extraordinarily beautiful, with sandy beaches stretching for miles and coral reefs offshore – the quintessential tropical paradise. Tourists come in the thousands to soak up the sun and swim in the clear waters around Roatan.
However, the sun-kissed beaches and cruise ships are only one side of the story. Until relatively recently, the island struggled to keep pace with its increasing popularity, due to its unreliable electricity supply. A change of ownership at Roatan Electric Company (RECO), the island’s private electricity utility, brought a vision of a better future.
The island’s power supply was improved considerably in 2017, after RECO contracted Wärtsilä to install four 7MW Wärtsilä 34SG-LPG engines that run on propane. The introduction of these power generation assets gave the island the confidence and ability to improve and add to the outdated island infrastructure, from streetlights to roads. Flexible power generation solutions, such as these 34SG-LPG engines, provide the required operational flexibility (including fast starting and loading capabilities) and speed up the transition towards a future powered by 100% renewable energy sources.
The next stage in Roatan’s energy journey is about to begin as RECO has shifted its focus to improving the reliability of the island’s electricity supply using today’s technology. It also heralds a clear path for switching to renewables and improving grid stability all at the same time.
“Our new goal is to pivot the electricity system towards sustainable, renewable energy production, incorporating the latest clean, smart and flexible technologies while harnessing our spinning reserve component to make a more efficient power gen operation,” expressed Ramiro Tumbaco, General Manager, Roatan Electric Company.
RECO has also started construction on a 7MW photovoltaic solar plant on the south side of the island and is planning another 5 MW solar plant on the north side of the island. These solar-powered plants, coupled with 4MW of existing wind power capacity, set the island on the path to achieving its goal of having 20% of its power supplied by renewable resources by the end of 2021.
RECO again turned to Wärtsilä for the final piece of the puzzle – a 10MW/26 MWh energy storage solution including Wärtsilä’s GEMS energy management system. These smart storage solutions will be installed alongside the island’s south solar park and are the key to bringing reliability to the island’s electricity supply and further integrating renewable resources.
The energy storage system is essentially a highly sophisticated battery that will be charged by the solar power plants. Stored electricity from solar power will mean that the existing generators are no longer needed to provide ‘spinning reserve’.
Spinning reserve is when engines idle on standby in case they need to produce extra power for the grid. With the battery system covering the spinning reserve, the diesel engines will be able to be switched off, saving on expensive fuel, reducing emissions, and eventually can be retired completely.
All the island’s energy resources will be controlled by GEMS from day one, including 10MW of batteries, the south solar park, and the propane engines. GEMS will seamlessly optimise the dispatching of a reliable supply of electricity across the island, which widely fluctuates as the island’s population swells from 60,000 to more than double, at 160,000+ during the holiday season. When the solar park on the north side is complete, it too will be integrated into the portfolio controlled by GEMS.
Because GEMS enables the integration of component neutral technology, any future resources that RECO decides to install on the island and accompany the utility on its renewable journey can be incorporated seamlessly.
As part of the contract, Wärtsilä is providing training to RECO to operate the GEMS control system. The system is designed to be user-friendly for operators and owners and is preconfigured to ensure it can respond to a range of scenarios that could possibly be encountered by the utility.
Christian Wang, Wärtsilä’s lead software engineer on the project, explains: “We do lots of simulations. We create a ‘digital twin’ of the island and run various load/availability scenarios to make sure the system responds correctly in those cases. The system is set up for 90% of possible scenarios, and we can remotely tune the parameters and make any corrections.”
Such scenarios ensure the system maximises the optimal use of resources and the best use of the battery. It also assures a fast recovery in the case of any asset going suddenly offline, or an unexpected event such as a tree branch falling on a power line.
Data is key, with load forecasting ensuring that progressively more accurate modelling improves the running of the system. Weather forecasting data is fed in so the system can anticipate the likely renewable output and adjust the operation of the various assets accordingly.
Specifically, the system builds accurate daily load patterns and schedules the turning on and off the engines to match likely renewable production, while also (dis)charging the battery in an optimal way.
Cassandra Heller, Business Development Manager in Wärtsilä’s Energy Storage & Optimisation team, adds: “The fact that we can tune the parameters and correct the system was a big point for the customer, in both the contract and the long-term service agreement. It was very important to have a user-friendly system for the operators. Having our expertise on hand puts the customer’s mind at ease.”
The impact of having a reliable and plentiful electricity supply on Roatan cannot be overstated, not only for the islanders, but for the economy as well. The island has some of the best diving and fishing in the world and is already a favored destination for U.S. cruise ships and the setting for the Caribbean Cup, an international deep-diving competition.
Now the roads are paved, the streetlights installed, and there is a diminished threat of a blackout, the potential to attract more tourists and more investment from resorts is enhanced. With Wärtsilä’s smart energy storage technology and controls, alongside flexible and fast-acting LPG power generation, RECO can continue to support the island’s development with sustainable electricity, integrating further renewable power sources as time goes on. To this end, RECO stands ready to meet future electricity needs as it had the foresight to plan for the need to increase supply as part of its overhaul project.
“The Roatan model is one that other Caribbean islands, similarly, blessed with abundant renewable resources can learn from. The combination of optimisation and control of assets with renewables and energy storage enables islands to move from underdevelopment to the state-of-the-art technology in step with others around the world,” stated Matthew Harper, Director of Operations, Roatan Electric Company.
