Close the Gap: How to revive lagging large-scale PV project performance

Alencon’s SPOT X2 DC-to-DC optimizer

Alencon’s SPOT X2 DC-to-DC optimizer can boost utility-scale PV plant performance.

A completed PV project is like a splashy free agent sports signing. Everyone is all pumped up at the ribbon cutting or press conference, but if it underperforms and misses expectations, that goodwill is gone. Live up to that contract or get booed.

In a world where new utility-scale projects might slow down (a possible understatement if tariffs are placed on module and cell imports), optimizing current portfolios is crucial, not just for each project to hit its targets, but to continue to prove solar as a worthy investment and distributed resource.

Closing Performance Gaps

With more than a decade of hardcore O&M industry experience, there is a greater reservoir of institutional knowledge both out in the field and in plant operation management. For example, MaxGen is a U.S.-centric O&M provider focused on utility and C&I sites that manages a large team of licensed, professional technicians throughout the country, hitting about 5,000 different sites a year for corrective (CM) and preventive maintenance (PM).

As part of its business model, the company will take over portfolios of assets to monitor — some of which are underperforming. According to Mark McLanahan, CEO of MaxGen, assets are usually underperforming because of one or more of these reasons:

  1. The site is not in good physical condition because of poor vegetation management or erosion or general site management. Consider this a reminder to keep O&M in mind when designing a project because it is often the largest expense over the life of the project. “Handling stuff like vegetation management and module washing can be the biggest expense by far if you’re not careful,” McLanahan says.
  2. Poor PM records, which often means PM hasn’t been done. “That’s a problem because you have to perform PM to maintain warranties of inverters, combiners and modules,” McLanahan says. “We have seen many cases where service to date is either not verified or there’s no record.”
    This is where PowerFactors comes in handy. PowerFactors is an energy operations management software platform that MaxGen has been using since 2016 to integrate all the monitoring, alarm management, work order creation and management, dispatch and reporting for all the operations, and preventive and corrective maintenance tasks in its scope of work with its customers. Also, contract requirements can be programmed into the system. For example, Power Purchase Agreements in California often require instant notification of large drops in capacity and failure to do this will incur penalties. Auto-notifications can be routed to the right places in those events with the right rules plugged into the software. This enables fewer operators to manage more projects with greater complexity.
  3. The site data acquisition system simply hasn’t been mapped properly, which undermines the data quality of the entire project and leads to maintenance misdirection. There’s an outage on inverter A; a dispatched technician heads to inverter B because it’s mapped as inverter A. The issue isn’t discovered, and so on. McLanahan estimates that MaxGen encounters this in 20 to 30 percent of the underperforming sites it takes over.
    “It’s a data quality issue,” he says. “With solar, you have to study performance at the low level, not just the revenue meter, to make decisions on performance. You have to look at inverters or combiners or at the main circuit. If the mapping is no good, you’re wasting time.”

Once the site is remapped and the PM is up to date, annual maintenance and CM plans are put in place to build it back to baseline performance using better data. From there, more advanced decisions can be made. Data can be studied for factors such as ground coverage ratios, tracker angles, performance anomalies at the combiner level and similarity-based modeling to help identify additional opportunities. MaxGen has boosted a number of utility-scale projects 2 to 5 percent on the performance side using this systematic process.

“With consistency, you’ll see 1 to 3 percent improvement right off the bat just with low-hanging fruit,” McLanahan says. “Compare the combiners on a relative basis on performance and just look at last month. That sets the corrective maintenance for the next week. Once you have accomplished all the PM tasks, have good data access and capture the low hanging fruit, you can move up the lost energy priority list and tackle the things that are above the baseline to increase production and revenue even further.”

Solar for All: How to incentivize community solar projects to benefit low-, middle-income customers

Retrofitting or Repowering?

Traditionally, the two options for a lagging PV site to hit its expected performance target are: 1) boosting its actuals, or 2) lowering the expected numbers.

“Once a project has been reviewed to ensure all the basics are correct, we can focus on boosting output to outperform proforma expectations. Part of this process sometimes includes resetting the baseline based on correcting performance assumptions made before the plant was built,” McLanahan says.

Obviously no one wants the latter, but overestimates happen frequently during the high-stakes, quick turn-time bidding process via incorrect assumptions regarding soiling, degradation, line losses, etc.

But, what if there was a way to still overachieve from the original estimates? This is the proposition presented by large-scale, DC-to-DC optimizers just now coming onto the market as part of a retrofitting strategy. The Alencon SPOT X2 is one such optimizer that has been recast in a manner to make it easier to minimize the soft costs — such as labor and ancillary installation materials — associated with PV retrofits. Minimizing installation costs is key to achieving the highest rate of return on PV retrofits, and retrofitting a PV plant with Alencon’s SPOT can significantly increase PV yield by introducing more granular MPPT while at the same time improving safety and decreasing on-going O&M costs.

“With a number of PV assets now changing hands as PV plants get older and PV fleets get consolidated, we are seeing a great deal of interest in retrofitting PV plants to improve energy yield. The SPOT X2 makes performing larger commercial and industrial or utility scale PV retrofits much easier than ever before,” says Hanan Fishman, president of Alencon Systems.

Now, retrofitting a large-scale PV system with new equipment is a tough sell because the profit margins are thinner and ROI is tighter than new construction (plus the downtime that must be factored in), but going this route with an experienced team could prove valuable. Energy and electrical systems specialty firm ProtoGen, for example, has executed a number of retrofit projects and incorporated Alencon’s SPOT DC optimizer at the string level to minimize those retrofit costs because it’s as close to a plug-and-play PV retrofit solution as possible.

“The key to pulling off a PV retrofit in a cost and time effective manner is to think in terms of 80 percent planning and 20 percent execution,” Fishman says. “In our experience, if you can maintain that proportionality, you should be able to set a similar target for your percentage of hard costs to soft costs.

Here’s a checklist Alencon suggests using if you are considering a retrofit for a large-scale PV project:

  1. How much is the equipment going to cost?
  2. Have I considered all the elements of ROI that go into the project including production incentives and potential tax credits like accelerated depreciation?
  3. What sort of engineering analysis will I need for the project? Structural? Electrical? Anything else?
  4. Will the work require a permit? If so, who is the AHJ? What do they need to approve the project (i.e. stamped and sealed drawings or just a statement of work)?
  5. What sort of certifications will be needed for the equipment being installed (i.e. UL or NEC)?

Bottom Line

The true bottom line in PV system performance, from initial projections to 30 years in the future, is customer service. People need to make the correct assumptions, perform all O&M tasks correctly and use data analysis to their advantage while being as proactive as possible. As more data is gathered and algorithms are perfected, “trend events” will be the next frontier for improving performance.

“These don’t show up as a discrete one-time energy loss but as small events that happen continuously over time, and if you don’t look for them you won’t see them,” McLanahan says. So, maybe one inverter is coming on and offline in mere seconds. “If you look at the curve, you won’t see it, but if you look at the trend, there’s something wrong with that inverter, and it will likely break down at some point.”

That curve is a nice visual to end on. Just plan to stay ahead of it.


 

Speaking of data…

Chris Crowell and Kate Trono, VP of Products for SunLink

Craving some more nerdy solar data talk? You’ll want to check out our new podcast — Solar Builder Buzz — in which we grab a beer with people smarter than us to discuss the solar industry. In Episode 2, we sit down with Kate Trono, VP of Products for SunLink, and pick her brain on the value of data in the solar industry and just where the industry is going (and should be going) from here. We maybe also discuss Sci-Fi.

Listen to the pocast here.


 

Take a quick peek

Measure launched new turnkey solutions for solar facility owners

Measure launched new turnkey solutions for solar facility owners, asset managers and O&M contractors that include drone-based site overview and maintenance, site shading and terrain analysis, thermal inverter scans, tracker misalignment detection and vegetation management. On a site generating 21 MW, for example, Measure can complete an inspection in seven hours instead of weeks, freeing employees and contractors for higher-value activities while also lowering inspection costs. The lower cost also makes it possible to perform more frequent inspections that can detect problems in a timely manner.

Maximum revenue capture for larger plants may not be inspected in a single visit and potentially leave some issues or faults unidentified. Measure’s launch customer was able to avoid a potential revenue loss through an inspection that discovered over 200 malfunctioning panels on a new solar farm.

— Solar Builder magazine

PV Pointer: Why mass-customized solutions win in utility-scale solar

SunLink

SunLink started designing solar mounting systems in 2004 when the concept of commercial rooftop solar was novel. The first systems were custom designed for the particular application because everything was new. Needless to say these first arrays were inordinately expensive by today’s standards, but the success of those installations helped pave the way for a booming distributed energy economy.

The early rooftop systems were engineered as a single structure where every solar module was linked together, efficiently distributing wind loads. In fact, SunLink’s name was inspired by the structural links holding the system together, which is how our Precision system still works.

Solar, however, is relentlessly cost competitive. Smaller installations can’t absorb the soft cost of custom engineering. At the same time, no two solar projects are the same, which on the surface mandates custom engineering. Mass customization can make customization at scale cost effective.

What is mass customization?

I often use Legos to describe mass customization. The Legos are standard, but you can configure the blocks to build whatever you want. Here are a few examples of this approach working in utility solar.

Take a single-axis tracker. The tracker needs to be engineered for a wide range of environmental conditions and any row length (since string length varies by project and space constraints require partial rows). This could lead to countless combinations of torque tube lengths and thicknesses. In a mass customized solution, a half dozen or so standard torque tubes are configured to meet the unique needs of the project. Limiting the number of parts greatly increases supply chain and engineering efficiency.

Similarly, the number of foundations can be increased to boost load capacity without designing a new part. Cleverly designed module mounting hardware accommodates the most common PV modules with no changes. The unique nature of solar sites is designed into products so that manufacturers can respond to opportunities quickly, cost-effectively, and with a fully-vetted solution. SunLink’s TechTrack dynamic stabilization feature is an example, which is a new tool for efficiently configuring resistance to wind loads.

Innovative manufacturers are moving beyond traditional racking and into software and services. In doing so the focus shifts from catering to the unique needs of the project to the unique needs of the customer, yet the benefits of mass customization remain.

PV Pointers: How dynamic systems increase the value of a solar project

As an example, SunLink recently launched product packages to complement its mounting systems. What differentiates the product packages is that they integrate hardware, software and services to serve a customer’s specific needs. The TechTrack Standard Package, Cold Weather Package and Pro Package allow for standardized solutions for common needs while giving the customer choice in what to pay for.

The product packages are analogous to the options available when buying a car. Paint color, drivetrain and interior options cater to different customers, but all are built from the base model car.

Mass customization also guides the development of software. Different modules are implemented depending on whether the user is an O&M provider, an EPC or a developer. The best systems are highly flexible with provisions to connect to a wide variety of data monitoring systems, device types, SCADA implementations, etc., because inverters, trackers, storage systems and other intelligent hardware are constantly changing, as are the requirements of the utility and the ISO.

Modern communication protocols are critical to strong yet flexible systems. Modbus, developed in the late ’70s and early ’80s, is still the most common protocol for energy devices and SCADA systems. It should be no surprise, however, that a 30-year-old protocol isn’t up to the task of two-way communication between thousands of modern intelligent devices and numerous software services. Worse still, many software packages have limited ability to communicate with other applications. If you want to look at the performance of a solar portfolio but have several data monitoring systems, you may be forced to print reports from each system and manually input the data into a spreadsheet. This is a failure of technology.

In tech, RESTful API enables efficient, flexible communication between devices and services and allows developers to build applications leveraging other applications. We’re now seeing APIs used in inverters, trackers, data monitoring systems and initiatives like Orange Button for bankability data to unlock new value in the energy industry.

Mass-customized solutions win in utility solar because they drive down cost while accommodating the needs of the project and customer. The next time you are looking at the design of a solar plant, or anything else for that matter, I encourage you to consider what’s led the products to be standardized, customized or mass customized.

As Director of Project Management, Patrick Keelin helps define SunLink’s next generation of products and services. His focus includes dynamic tracker design, IoT and the role technology plays in R&D, design and long-term solar project economics.

— Solar Builder magazine

Solar for All: How to incentivize community solar projects to benefit low-, middle-income customers

Geronimo Energy

Geronimo Energy celebrating another community solar install in Minnesota.

Community solar has taken off within the renewable energy development leagues, melding the interests of residential and commercial or industrial customers, as well as the local utilities. While the inclusion of low- and middle-income (LMI) residential customers are widely enabled by state legislation on community solar, specific carve-outs or percentage requirements for LMI customers are less common. At times, solar developers have focused heavily on anchor commercial or industrial customers and paid little attention to residential participation, much less the LMI segment.

While the LMI customer segment may present something of a credit challenge in developing a project, anchor tenants can readily compensate for the project risk. Indeed, a 2016 study by the Interstate Renewable Energy Council (IREC) found that economically viable community solar programs could include 40 percent LMI customers.

When there is local, state or federal funding for LMI customers, like HUD Block Grants, developers have added inspiration to include the segment, but such funding is not always readily available, or the lengthy paperwork may seem to outweigh the potential benefit of the revenue stream.

To help remedy this practice of under-weighting LMI customers in community solar development, local housing authorities have stepped up to bring their resources — if not regulations — to bear, early in the planning process. Developers also have found that the housing authorities and other social institutions can be valuable partners in locating and enrolling customers in a project well ahead of ground-breaking.

Local Leadership

As of August, 14 states had passed legislation to enable community solar, according to one recent analysis. Among these, Minnesota is ground-zero for community solar evolution in the United States and leads the nation in community solar projects. An estimated 400 MW of community solar is in the pipeline in Minnesota, which is now grappling with how to provide interconnection services for such a groundswell. One early developer of community solar in the state is Edina-based Geronimo Energy.

“For our new 50-MW Nordic portfolio of community solar projects, we approached the St. Paul Public Housing Authority and they got involved in the process, learning how much they could save and pass on to their residents. As a result, they were very helpful in the pre-sales stage,” says Lindsay Smith, the director of marketing and communications for Geronimo, which recently sold a 100-MW community solar portfolio in Minnesota to Berkshire Hathaway.

Community Solar Legal Primer: From project structure to consumer protection

Since housing authorities generally subsidize the cost of energy for LMI residents in their programs, lower-cost energy translates into savings. “There is a huge economic advantage for these authorities to subscribe,” Smith says.

Other states also are tuned into the LMI segment too.

  • In Colorado, where there is a five percent LMI carve out, the Denver Housing Authority has been active in the facilitation of a 1.95-MW LMI project next to a landfill in Fort Collins. The project is being developed in collaboration with Oakland-based GRID Alternatives, Boulder-based Namasté Solar and a local electrical cooperative.
  • Maryland’s community solar statute requires that about 30 percent of project generation serves LMI households.
  • In New York, the initial stage of a state community solar program requires a 20 percent LMI customer participation. The state does not wield the stick without a carrot. NY Green Bank offers developers soft loans for the inclusion of LMI customers in solar developments.
  • A more local area initiative is underway at the Imperial Irrigation District (IID) in southern California in which IID is developing a new community solar project of up to 20 MW and working to establish a community storage project of up to 10 MW. The district says, to ensure all customers have access to the benefits of solar power, it is also working to create a separate low-income solar program specific to income-qualified customers.

GRID alternatives at work

Finding Financing

The potential for growth in community solar is enormous. Third-party-led solar — a.k.a. community solar — added about 85 MW in 2016, twice the 2015 total, and is expected to add 1.8 GW by 2021, according to a recent forecast by GTM Research. An even more optimistic forecast by the Rocky Mountain Institute suggests that community-scale solar could amount to 30 GW by 2020.

Perhaps the key limit to community solar growth with an LMI component is financing. One institution seeking to foster new financing approaches is the Rocky Mountain Institute’s Electricity Innovation Lab (e–Lab), which set up teams in June to develop new business models. One team included support from the Vermont Energy Investment Corporation (VEIC).

A more altruistic approach has been taken by Glenwood Springs, Colo.-based Alpine Bank, which bought shares in a Summit County community solar project and donated them to the Family & Intercultural Resource Center (FIRC), an agency that provides services for low-income residents. The organization managed solar credits on participants’ monthly bills.

The bank’s purchase was in part motivated by a low sign-up response from the LMI community, making it difficult to meet the 5 percent LMI carve-out. Alpine Bank worked with Clean Energy Collective to arrive at the donation solution. CEC has a portfolio-plus-pipeline of 175 projects with 33 utility partners across 15 states with over 400 MW of community solar capacity.

SunShot Support

DOE puts taxpayer money where its mouth is. “The enormous opportunity to expand solar electricity access to LMI households is why the SunShot Initiative launched the Solar in Your Community Challenge … building on the [Obama] White House’s Clean Energy Savings for All Initiative,” the agency noted in 2016. The initiative goal was to enable 1 GW of LMI solar by 2020.

This year, the SunShot program took applications in January for $5 million in award money to form a team to design and deploy scalable community-based solar projects or programs up to 5 MW in 18 months that serve at least 20 percent LMI households or 60 percent non-profits, according to its website. Teams began work in May and are scheduled to have their community solar projects completed in October 2018.

The SunShot Initiative is a founding member of the National Community Solar Partnership that works to expand access to community and shared solar throughout the nation, especially in low- and moderate-income households. The partnership is a collaboration with the Department of Housing and Urban Development, the Environmental Protection Agency, the Department of Agriculture, and key representatives from solar companies, non-profit organizations, state and community leaders and financial institutions, the DOE states.

The U.S. Department of Energy has lofty aspirations for the LMI segment in community solar.

“Community solar projects are gaining popularity as they allow the almost half of U.S. households that may not have access to a solar-ready roof to take advantage of the sun’s energy and do it at a lower cost. This can make solar accessible to more LMI communities,” the DOE’s Office of Energy Efficiency & Renewable Energy opined in November 2016. “Between 2010 and 2015, community solar installations grew rapidly, reaching almost 100 MW, and this business model has even greater potential. The U.S. National Renewable Energy Laboratory (NREL) estimates community solar could comprise up to half of the distributed PV market in 2020.”

Charles W. Thurston is a freelance writer covering solar energy from Northern California.

Solarize This: Nexamp adds more community solar in the northeast

Nexamp adds more community solar in the northeast

Nexamp completed a 700-kW community solar project in Fitchburg, Mass., through its Solarize My Bill community solar program. Participating Unitil Corp. customers, many of whom were previously unable to install solar panels on their own property, are now seeing reduced electricity charges through their subscription to the Fitchburg Solar project. In addition, the neighboring Town of Lunenburg will realize substantial energy cost savings through a long-term agreement to purchase discounted energy credits generated by the project. Fitchburg Solar is one of 17 community solar facilities that Nexamp has constructed and expects to achieve operations in the coming months.

“Lunenburg has enjoyed a very beneficial relationship with Nexamp,” said Phyllis Luck, Board of Selectman, Town of Lunenburg. “In addition to the town’s net metering agreement, which is expected to generate over $600,000 in utility cost savings over the next 20 years, Nexamp has extended the partnership to include our town’s residents, who remain keenly interested in community solar. In fact, Nexamp enrolled nearly 40 Lunenburg households in two weeks’ time to their Solarize My Bill community solar program, and these residents should save over $275,000 in electricity costs over the term of their subscriptions with Nexamp.”

 

— Solar Builder magazine

Editor’s Choice Solar Projects of the Year: 6 projects that didn’t win, but we thought were cool

Innovation

Urban Health Plan “Solar Wall”

Urban Health Plan “Solar Wall”
Bronx, N.Y. | 37 kW

What to do in a crowded city with little to no roof space to add solar. Why not try something completely different? New York City solar installation leader Quixotic Systems designed an innovative solar solution in the heart of the Bronx at Urban Health Plan’s Simpson Pavilion. Unlike most rooftop systems, the 37-kW array has been installed on the side of the building — a “solar wall.” The PV system designed and installed by the team at Quixotic foregoes limited roof space in favor of the Bronx building’s south-facing four-story façade. The high-efficiency array features 104 SunPower 327 panels mounted on a custom vertical rack and connected into Fronius inverters. The solar installation will offset the center’s energy use by 10 percent, saving an estimated $230,000 over the next 25 years.

Cool Technology

Three Peaks Solar Three Peaks Solar

Three Peaks Solar
Cedar City, Utah | 107.7 MWdc

Three Peaks Solar is an 80-MW solar facility and 138-kV substation that sits on 739 acres in Cedar City, Utah, developed by Clēnera. The facility was Swinerton Renewable Energy’s (SRE) first 1,500-volt system and one of the first projects in the United States to feature SMA’s 2500 EV inverters. Swinerton worked closely with NEXTracker to develop and customize a unique module rail, which significantly reduced the installation time and allowed for an aesthetically pleasing finished product. Three Peaks was also the first project to utilize SRE’s new production and quality tracking app, Sunscreen. The software allows for real-time tracking of construction progress and gives all stakeholders 24/7 access to vital construction metrics (daily install quantities, total install quantities, overall project completion percentage, open QAQC items, fixed QAQC items and QAQC reports). More than 98 percent of the labor came from local hires.

Job creation

Kayenta Solar Project

Kayenta Solar Project
Kayenta Monument Valley, Ariz. | 37.6 MWdc

At the gateway to Monument Valley, 300 miles north of Phoenix, the Kayenta Solar Project is the first and the largest solar power plant in the Navajo Nation. Developed by the Navajo Tribal Utility Authority (NTUA), the project’s parameters were strict, requiring that most of the construction team be members of the Navajo Nation and that the natural landscape be preserved during installation. So, yes, during the harsh desert winter, tracker supplier Soltec recruited and trained 188 members of the local community (98 percent of the workforce) on both tracker and foundation installations and the mechanical assembly of the plant’s modules. This workforce was able to finish the project in only 3.5 months, and a large number of Navajos joined the Soltec team for subsequent projects. To maintain the natural environment of the sacred land during installation, Soltec’s SF Utility Tracker was deployed, which limits grading on land and requires 46 percent fewer piles.

Problem-Solving

Elizabeth Mines in 1958

Elizabeth Mine Solar Project

Elizabeth Mine Solar Project
Orange County, Vt. | 7 MWdc

The Elizabeth Mine is a famous copper and iron sulfate mine that was listed as a Superfund site due to acid mine drainage discharging from discarded waste rock that hurt water quality downstream. Superfund sites pose unique challenges in terms of financing, organization and paperwork, but for developers Brightfields Development, Wolfe Energy, Greenwood Energy and the Conti Group, planning and designing the PV system for the Elizabeth Mine Solar Project was another huge hurdle. It needed to be constructed on top of the environmental cap without damaging the impervious liner that prevented rainwater from washing through the tailings pile. Multiple iterations of module selection, inverters, ballast sizing and racking were made to maximize the project output while meeting the pressure limits on the cap system, as well as meeting storm water regulatory requirements. Since Solar FlexRack’s pre-cast ballasted system was selected to protect the installed remedial environmental cap — 2,288 of these solar racking foundation blocks were loaded and transported over a steep ridgeline and down a narrow winding road to the remote rural site location.

A large solar plant located in a remote rural area also created challenges for both communication and interconnection, which included an upgrade of approximately four miles of utility lines, 10 miles of dedicated fiber-optic communications line and an upgrade to the regional substation. Green Mountain Power also upgraded three phase lines up through the town of Strafford as part of its reliability improvement program. The changes, in total, benefited the community with an improved electrical system that upgraded the reliability of the entire system.

Carver Solar

9458 Carver Solar
Carver, Mass. | 1.142 MWdc

For S&C Electric Company, Synergy Solar Inc. and RBI Solar, construction on this active cranberry plant bog required some unique installation techniques, like using plywood matting to protect the plants and ramps for egress into the bog area, but the outcome is a big win for the farm and proving a PV mounting concept from RBI. Some have argued that installing solar on usable farmland renders the land useless for agriculture, but solar farms like Carver are proving that going solar doesn’t have to mean giving up growing. In this case, the ground-mount solar installation benefits both the cranberries and the farm. Shade from the solar modules actually provides an ideal growing environment for the berries underneath. At the same time, the 1.1-MW ground-mount system is harvesting clean energy of its own to power the farm’s operations.

Cuttyhunk Island

Cuttyhunk Island
Cuttyhunk Island, Mass. | 348 kW

With a modest year-round population, Cuttyhunk Island, the westernmost of the Elizabeth Islands chain that lies between Martha’s Vineyard and the south coast of Massachusetts, could never justify an undersea utility cable from the mainland and has depended on diesel generators. As the island’s popularity increased, it made more financial sense for the island to go solar. Solar Design Associates developed a solar + storage/generator hybrid microgrid. The resulting black-start-capable system includes 350 kWp of PV and 1.25 MWh of storage capacity to provide the primary source of power for the island, satisfying the majority of annual requirements. The system runs in parallel with the existing gensets during periods of low sun. The island was, obviously, accessible only by boat, so a post driver, rock drill, two truckloads of racking material, six crew members and all other construction equipment had to arrive via barge. The mechanical scope of the project (posts, RBI racking and SolarWorld module install) was completed in 21 days. Now, the island gets about half of its electricity from the solar array during peak season.

— Solar Builder magazine

Solar Builder Project of the Year C&I: Worcester Greenwood Landfill

Worcester Greenwood Landfill

How’s this for timing: Environmental Protection Agency Administrator Scott Pruitt made headlines, as we were writing this, for proudly proclaiming that he would get rid of the tax credits for the solar industry. Let that marinate as we tout the virtues of our Commercial & Industrial Project of the Year Award winner.

Developer: Honeywell • Contractor: Borrego Solar Systems • Modules: LG Electronics • Inverter: SunGrow • Mounting: SunLink

Stretching across 25 acres (19 football fields), the Greenwood Street Solar Array is the largest municipally owned landfill project in New England. The city signed an energy savings performance contract with Honeywell in 2011 that targeted to bring renewable energy to 92 city-owned facilities, and this $27 million project is expected to pay for itself in six years and save the city $60 million over its expected 30-year life span. It will produce enough clean energy to power 1,340 homes per year.

Because the solar array is municipally owned, it allows Worcester to sell the electricity at net-metering rates. The city also paired this project with an initiative to replace 14,000 street lights with LED bulbs to reduce energy demands while also infusing renewable capacity.

Tough to argue against that value to the city, but then consider the land used for the project was a landfill — an unusable swath of earth; a blight on the community — that is now actively being used to power homes. In order to protect the integrity of the landfill cap, SunLink and Borrego worked closely together to ensure that loads superimposed by the array will not exceed allowable limits at any time, including heavy snow and wind events. SunLink’s GeoPro systems come with terrain adjustability designed in, allowing the array to easily adapt to existing site conditions without grading work.

“The next time you hear someone say, ‘what are we doing for the taxpayers,’ tell them to look up on the old Greenwood Street landfill,” said City Manager Edward Augustus Jr. at the ribbon cutting.

Or, as Worcester Mayor Joseph Petty summed it up: “This project makes good environmental sense and fiscal sense. It’s just one of the ways we as a city are planning for decades to come.”

Anyway, we’d be curious to know how the head of our environment’s protection would object to incentivizing more projects like Worcester Greenwood Landfill.

— Solar Builder magazine