Unsubsidised, commercial solar-plus-storage projects of the type being executed in Puerto Rico could demonstrate how to overcome many of the challenges imminent for the world’s PV markets, according to one company with experience in the field.
Antonio Montoto, a business analyst with GP Tech, which specialises in power technology and energy management, told PV Tech's sister site, Energy Storage News, that two projects his company has worked on, including a 50MW PV plant paired with 22MW of storage capacity, are helping prove that while getting maximum value for storage is complex, the challenges can be overcome.
Renewable energy projects in Puerto Rico must comply with minimum technical requirements (MTR) to allow for their integration into the island’s grid. Developers must provide the equivalent to 30% of its nameplate capacity in storage for frequency regulation over a 10-minute duration. They must also provide 45% of the equivalent to the system’s nameplate, for one-minute ramping.
O&M of storage has critical impact on system economics and lifetime
Montoto told Energy Storage News that projects delivered to meet these requirements can show how to overcome the technical complexities of controlling energy storage for optimum performance and system lifetime. Such projects are also showing the wider world including developers that the operations and maintenance (O&M) of grid-connected storage systems is a more critical part of the business model than might have previously been expected, Montoto said.
“It's critical to have storage to obtain the ramp down of the ramp control. For the frequency control you can use oversized PV plants, but you can maximise the use of the storage if you use the active power of the storage to control the frequency. When there is a variation of the frequencies you can join 4MW of the storage with 10MW of the solar, so you get complete regulation without losing the charge.”
GP Tech focuses on grid integration of solar and wind, as well as grid stability and energy for transportation, producing its own power integration, energy management, plug and play storage solutions and solar inverters at various levels.
Explaining that the Puerto Rico projects are unsubsidised, Montoto said it is vital that storage systems return optimum value for their use to be economical as well as technically adequate.
“What is not clear sometimes is the [required] O&M. [This is a] commercial project, no subsidies and it’s not a pilot.
“So to obtain approval from different banks, we needed to demonstrate that the storage facility will be performing in a deterministic way from the moment of the beginning up to 10 years before any refurbishment.”
GP Tech has partnered with PV Tech to present a webinar, “Grid-interactive energy storage systems: Insights from real deployment in MW-scale renewable facilities”, on 21 April.
Taking as case studies three of the company’s utility-scale projects which are all different in scope, two in Puerto Rico and another in New Orleans, the webinar will look at topics such as control of systems – including utility control – and the “different behaviour” of storage in microgrid, on-grid and hybrid configurations.
It will also look at issues such as the different dynamics and drivers for storage in various regions of the world and how this is forecasted to change, including the utilities and developers that are currently doing a lot of the work others will look to as a reference in years to come. It will also look at the economic importance of knowing what the technological options are for differing applications.
“[People often] think about the advantage of the storage, but not the complexity of controlling it,” Antonio Montoto said.
“Many people are put off by this sort of complexity and they think perhaps it is too early to get involved with this technology. Integrating it into the project is difficult but we want to demonstrate with this successful case that it can be done.
The session will give participants control of an interactive 3D model of one of the Puerto Rico plants, the 11MW Salinas PV facility, which is paired with 5MW of storage. It will be presented by GP Tech’s CEO, Javier Landero and company CTO Sergio Hurtado.
To attend the webinar on Thursday, 21 April, 4:30pm London time, register free here.