Slate solar-plus-storage in California, which incorporates over 560MWh of battery alongside 300MW of PV. Image: Recurrent Energy.
Solar and energy storage had been described by Elon Musk as going collectively “like peanut butter and jelly”. Andy Colthorpe meets among the gamers creating this profitable mixture within the US.
First, some fast stats: out of 10GW of battery storage additions deliberate for deployment in US utility service areas over the following two years —round 60% — is paired with solar, in accordance with figures from the US Energy Information Administration (EIA) launched in March.
Solar-plus-storage is changing into a large a part of the renewable energy market within the US. In Volume 28 of PV Tech Power, Lawrence Berkeley National Laboratory (Berkeley Lab) researcher Will Gorman famous that as of the tip of 2020, there was a couple of gigawatt of solar-plus-storage in operation at 70 websites.
Then, utility interconnection queues, Berkeley Lab discovered 160GW of solar PV being developed that was paired with batteries. Of course, not all of this will probably be constructed by a protracted shot and positively given the challenges of securing interconnection a few of it will not be constructed for a number of years, however clearly rather a lot will.
If you haven’t learn Gorman’s article, we’d urge you to return and achieve this. Among the fascinating insights is the assertion that hybrid assets — pairing energy storage with solar or wind (or each) — isn’t all the time one of the best resolution versus standalone.
The excessive worth of a grid interconnection level that the renewable and batteries can use, in addition to the federal funding tax credit score (ITC) incentive which applies to solar-plus-storage however to not standalone storage, are robust drivers for the exceptional development in curiosity in hybridisation.
But after all, in lots of instances solar-plus-storage does work very effectively certainly — amongst Elon Musk’s many pronouncements was a then-famous 2016 quote that the pairing is like “peanut butter and jelly”.
We spoke with 4 corporations which are placing that metaphorical sandwich collectively within the subject. Broadly talking, they’re lively in two scales of solar-plus-storage: very giant utility-scale power crops and smaller distributed technology tasks.
Lucas Moller is head of energy storage at Recurrent Energy, the US-based developer subsidiary of Canadian Solar. Recurrent develops large-scale crops, together with Slate in California: 300MW PV with 140.25MW/561MWh of BESS, which the corporate offered to Goldman Sachs and got here on-line in March.
Jamal Burki is president and Joonki Song VP of promoting and provide chain administration at IHI Terrasun Solutions. The full lifecycle providers supplier for solar-plus-storage is a subsidiary of Japanese conglomerate IHI, presently engaged on the US$1.2 billion Gemini undertaking in Nevada for developer Primergy.
Mark Frigo is VP for energy storage at Nexamp. Known as a pacesetter in US group solar, based mostly on the East Coast, the corporate is creating a wave of solar-plus-storage tasks at a extra distributed degree in key markets like Massachusetts.
Mary Caldwell is VP of product advertising and marketing at good energy storage know-how and providers supplier Stem Inc. From a background delivering behind-the-meter batteries — and solar — for industrial and industrial (C&I) prospects, Stem Inc is now additionally in energy storage procurement, integration and operations for distributed degree solar-plus-storage, each in entrance of and behind-the-meter.
Recurrent Energy – Lucas Moller
“Solar-plus-storage for us to date in terms of executed projects is all California, is the case for most of the market. But, fundamentally, we look at all solar projects in our portfolio as potentially solar-plus-storage. That’s just our perspective on how we do project development and plan for future market demands — not today’s demands,” Lucas Moller says.
While it looks as if solar-plus-storage has sprung up in California nearly in a single day, in truth it was builders like Recurrent taking that perspective early on which has made it so. Moller refers to Slate, the “star project of sorts”.
Slate was conceived as a solar-plus-storage undertaking from 2015 when interconnection plans had been drafted up. Even additional again, interconnection requests for solar tasks filed by the developer in 2014 included storage.
That “first flag planted” highlighted that the areas giant solar tasks had been being developed in would have sufficient variable solar technology to want storage to shift energy into later hours sooner somewhat than later. While the economics didn’t pencil out for solar-plus-storage then, Recurrent knew they might earlier than lengthy.
“We look at all solar projects as solar-plus-storage projects. As it pertains to California, and [more broadly] the Desert Southwest US, there’s no such thing as a solar-only project anymore. There is pretty much a fundamental need to add storage to every project to make it economically viable.”
In different phrases, the worth of solar-plus-storage is immediately related to the diploma of solar penetration.
“The reference, after all, is the duck curve, which is essentially driving worth in energy shifting. That is creating necessity for storage, however additional than that, it’s saying any marginal solar that comes on-line must successfully ameliorate the very low or generally adverse worth of noon energy. So, we don’t wish to create a brand new power plant that’s primarily going to be stranded on the market injecting low worth power in the course of the day if it’s a standalone PV asset.
For the patrons in these markets, whether or not it’s a regulated market like Arizona or an open market in California, the worth of that noon energy is so low in each marginal megawatt of renewable power that while you purchase a brand new plant, you need it to be related to the flexibility to shift and never be uncovered to that low worth in the course of the day.”
IHI Terrasun – Jamil Burki and Joonki Song
“Four years back, if you did a 50MWh project, you would do a big press release and hold an event. With Gemini, a 1.4GWh, DC-coupled, solar-plus-storage, solar-only charging project, it’s really a milestone project that we’re working with Primergy on,” Jamal Burki says.
IHI Terrasun can also be concerned with among the smaller, distributed technology tasks — together with a just lately accomplished undertaking in New England ISO territory for Nexamp — and whereas these are worthy of celebration in their very own manner, solar-plus-storage on the sheer scale of Gemini, which expenses from 690Mwac/966MWdc of PV, reveals “how the industry has really come together,” Burki says.
The four-hour length BESS at Gemini will present solar time shifting, taking cleanly generated power into the night peak. Joonki Song says Gemini and tasks prefer it present that the mixture of solar and storage creates dispatchable power crops.
They will not be 24/7 power crops, however they mix the 2 applied sciences to “provide consistent power from when the sun rises and capture energy when the solar generation is higher than the inverter limit and then smooth out in the afternoon”.
Conversely, one other large-scale undertaking IHI Terrasun is engaged on, Leeward in California (72MW of PV with 36MW/144MWh BESS), is AC-coupled.
“It’s really more of a peak shaving and interconnect firming application and the customer is also planning to use that for voltage regulation,” Burki says.
The variations in functions drive the choice to AC-couple or DC-couple: solar-plus-storage tasks supposed to offer numerous ancillary providers and grid stability will probably be AC-coupled, whereas DC-coupling is healthier fitted to doing numerous solar shifting.
Meanwhile, by way of know-how and system design solar-plus-storage is broadly talking extra advanced than standalone energy storage.
“If you have standalone energy storage, the controls are relatively simplistic. You have a signal coming in for charging the batteries from the grid, and a signal coming in for discharging it, so the controls piece is relatively straightforward,” Jamal Burki says.
Standalone storage’s two predominant use instances are to offer both short-term peak discount or ancillary providers, or each. As alluded to by Joonki Song, solar-plus-storage performs extra of a power plant position, however after all, the batteries there can even present different functions.
While standalone and solar-plus share some complexities round ensuring batteries are wholesome, state-of-charge administration is in place and so forth, for DC-coupled tasks particularly, there’s additionally a “lot of technology that needs to go in” to make sure solar PV in any other case clipped throughout instances when technology goes above that inverter restrict is captured effectively.
The market continues to evolve and Burki says “tremendous improvement” is being seen within the applied sciences, in batteries, however maybe much more so in inverters. All of the Tier 1 inverter corporations are already offering AC-coupled and rising numbers are including DC-coupling too.
Over the final three years, IHI Terrasun has doubled down on creating solar-plus-storage controls and monitoring for DC-coupled methods and partnered with two inverter corporations to convey options to market.
Where beforehand a solar-plus-storage undertaking was extra like two separate methods working facet by facet, built-in controls create “green power plants”: “so you can start to think in those terms — a dispatchable renewable solar power plant,” Burki says.
“We see that trend continuing and growing.”
An IHI Terrasun solar-plus-storage undertaking. Image: IHI Terrasun Solutions.
Nexamp – Mark Frigo
“If you’re in solar, you have to be in energy storage. They go together, like Yin and Yang,” Mark Frigo says.
Nexamp has been round since 2007 and began ramping up its energy storage efforts two or three years in the past, to the purpose the place it now has 140MW of distributed solar-plus-storage or standalone storage in development or in operations, largely within the northeastern US.
When requested if there could also be a ‘one size fits all’ resolution for US solar-plus-storage, the reply is “an emphatic no,” as a result of relying on which state your tasks are in and what alternatives they’ll goal, the batteries will be fixing totally different issues, Frigo says.
For occasion, two Nexamp tasks just lately introduced on-line in Massachusetts and paired with Nexamp group solar PV installations have 4 distinct revenues related to them.
“One, they’re part of a state programme called Solar Massachusetts Renewable Target (SMART). Two, they’re part of [another] state programme called Clean Peak. Three, they are a capacity resource and they are also a frequency regulation resource for the independent system operator, ISO New England.”
Elsewhere in New York, one other undertaking is being developed for a utility as a non-wires various to constructing out transmission and distribution infrastructure. It’s nonetheless paired with solar, however the energy storage’s predominant use case is to mitigate a substation overload within the utility’s service territory.
As Frigo describes it, there are solely a handful of US states which have put in place incentives and programmes to maneuver ahead the progress of unpolluted energy growth and related energy storage, Massachusetts, New York and California being prime examples.
Outside of these main areas, within the US market, there are typically two main drivers for solar-plus-storage. One is the ITC, which may decrease the capex value of the gear by as much as 30%.
Storage is eligible for the ITC if colocated with solar technology and charged a minimum of 75% to 100% of the time from that PV yearly. The nearer to 100% you get, the nearer to that full ITC capex discount you get.
“The reason for that is simple. The ITC is meant for renewable generation and if instead of charging from the solar, you charge from the grid, you have no idea of where that power is coming from,” Frigo says.
The different possibility is in creating what Nexamp calls “a shaped product”, adjusting the form of the solar technology curve to fulfill demand when most dear, usually within the early evenings and at different peak demand instances. By including storage, as an alternative of giving a buyer a take-as-is kind of power buy settlement (PPA), technology is supplied at totally different instances based mostly on the client want.
Frigo argues that the ITC needs to be prolonged to standalone storage, for cases the place pairing with solar doesn’t essentially make sense. However he additionally acknowledges that with batteries as a comparatively new phenomenon on the grid, these items take time to maneuver via regulatory and political steps. That consists of solar-plus-storage as a lot because it does standalone.
“This is what our planet needs,” Mary Cauwels says. Image: Stem Inc.
Stem Inc – Mary Cauwels
Focusing on Massachusetts, which targets web zero emissions by 2050, Stem Inc’s Mary Cauwels explains how the state makes use of the SMART programme in service of that objective.
SMART pays a per kilowatt-hour price for all solar manufacturing for a 20-year time period. Recently the administration of Governor Charlie Baker doubled its goal to three.2GW. It incentivises the addition of battery storage with state-provided funds, paid by the utility to the undertaking proprietor.
Massachusetts’ Clean Peak Energy Standard in the meantime incentivises clear energy tech that provides electrical energy or reduces grid demand throughout seasonal peak demand durations, as established by the state’s Department of Energy Resources (DOER).
For Stem Inc, as a California headquartered tech firm, it was a query of constructing on its expertise of delivering solar-plus-storage in its home marketplace for behind-the-meter industrial and industrial (C&I) prospects and adapting these choices for a market which is characterised by extra advanced — however rewarding — use instances.
That meant configuring the corporate’s Athena synthetic intelligence-driven software program platform and bidding algorithms to sort out functions that earn these 4 distinct income streams that Nexamp’s Mark Frigo referred to.
“We’re optimising charging the battery from the solar and then dispatching the solar, dispatching the batteries’ stored energy to the market, as appropriate, into the different value streams: for the wholesale market in ancillary services and forward capacity markets at the right time, so we can capture the full value of the solar,” Cauwels says.
Cauwels presents a easy income breakout of a solar-plus-storage system working in Massachusetts.
“We’re seeing about 34% of the revenues coming from the energy market. About 27% coming from forward capacity markets, 15% coming from real time reserves, 12% coming from clean peaks, and about 12% coming from frequency regulation. There’s a really interesting kind of spread across all these different value streams that solar-plus-storage is able to participate in.”
In the close to time period, Stem Inc sees a vibrant future opening up in Connecticut, the place regulators need 580MW of a 1,000MW energy storage deployment goal by 2030 coming from aggregated behind-the-meter methods. Hawaii will proceed to be a hotbed of solar-plus-storage because it has for years, pushed on particularly by Hawaiian Electric’s Battery Bonus incentive programme which simply received prolonged.
All of this pushes in the proper route. Cauwels says it is very important recognise how far the clear energy motion has include simply solar alone previously, and the way rather more will probably be carried out now energy storage has hit the mainstream.
In the final 5 to 10 years, with out energy storage numerous extra solar energy was generated and wasted, which means fossil fuels had been used to fulfill peak demand. With energy storage, extra clear energy will be absorbed, injected into the grid and add extra flexibility as increasingly renewable energy is built-in into the networks.
“This really helps shift loads better, absorb more low cost clean energy, during optimal times and really discharge energy, when more expensive greenhouse gas emitting conventional resources would have otherwise been used,” Cauwels says.
“This is what our planet needs. This is the purpose of what wind and solar are all about and storage is one of the answers to bringing that intermittent resource into play more responsibly.”
