Renewable energy could actually add more stability to electricity networks rather than hampering it, as the grid evolves toward greater levels of distributed generation, Enphase CEO Paul Nahi has said.
In an interview in London last week, Nahi told PV Tech that the ability to use data collected from PV systems to monitor and control or adjust the status of generation and load in a network is an example of how “solar assets” could be “leveraged” to understand grids better and react accordingly when something goes wrong or needs to be upgraded.
“The ability for renewables to actually add to grid stability is what I think is being missed by most individuals,” Nahi said.
The key, Nahi said, is that data collected by modern inverters and potentially by other parts of PV systems can be used to help utility companies or transmission and distribution (T&D) operators to manage networks.
“The grid was designed in more of a hub and spoke model where you’ve got central generation and everything heading in one direction out towards the loads and then usage. Now for the first time, not only do we have generation occurring at the end nodes, in the distribution and transmission line, but generation is now heading back into the grid.”
“The problem is that since the grid was never developed for this, there’s a view that by adding generation you don’t have visibility and the reverse flow of energy may have an adverse effect on particular transformers or even central generation facilities. But the reality is that no, with those solar assets out there, we can leverage those assets.”
Earlier this year, Enphase, which specialises in module-level microinverters, remotely upgraded 800,000 inverters at rooftop PV sites for Hawaiian Electric in the US Pacific Island state. The inverters were upgraded for voltage ride-through, allowing the PV systems to continue operating at a lower grid voltage than before. As an island state with both environmental and economic concerns about the use of fossil fuels for power generation, Hawaii is often seen as an exemplary test bed for what happens when regions begin reaching higher levels of renewable penetration. The state now even has in place a target of generating all of its power through renewables by 2045.
“What we did in Hawaii, the first thing we did is we showed them [Hawaiian Electric] what’s going on in their networks. It was a visibility that they did not have prior to that. The inverter itself is capable of providing data on the DC side, the panel side, of the inverter itself as well as the AC side, so I know exactly what’s happening with the grid, I can pick out particular waveforms, I can do a lot just in terms of visibility.
“So we were able to show Hawaiian Electric where the challenging spots were and where it wasn’t so challenging. They were able to open up a queue in the areas where it wasn’t so challenging, and in the areas where there were more issues – obviously with a lot of work with Hawaiian Electric – we were able to issue a command, with the proverbial push of a button, I would say almost literally a push of a button from our corporate offices, we were able to upgrade about 800,000 of our inverters to a new grid profile to help stabilise the grid.”
As the utility later said, the Enphase project saved Hawaiian Electric a substantial sum of money, thought to be in the tens of millions of dollars, over what it would have cost to physically visit each site, assess and upgrade the inverters.
Enphase has been evangelical about its devotion to data collection for some time. Nahi’s colleague and co-founder of the company, Raghu Belur, told PV Tech at the PV Expo show back in February that Enphase is constantly looking to use the vast amounts of data it collects through its installations in a number of ways to manage energy systems.
“We collect 850 Gbs of data per day, almost a terabyte of data per day on 250,000 systems in 80 countries. We have an incredible amount of intelligence out deep in the network that now we’re starting to leverage,” Belur said.
Enphase is also hoping that pairing solar with the company's AC battery, which the company expects to roll out gradually from the third quarter of this year, will add another level to this leveraging position.