Urban Planning: Commercial rooftops are biggest void, opportunity in solar

Standard Solar

Solar projects have so much potential when viewed as a collective bundle, like this group of 30 rooftop arrays Standard Solar is installing for the Washington, D.C., Department of General Services that combine for a total of 7 MW (pictured here).

Commercial rooftops offer a ton of potential job opportunities for solar installers and developers going forward. Analysts at the Energy Department’s National Renewable Energy Laboratory (NREL) estimate a technical potential of 1,118 GW of capacity and 1,432 TWh of annual energy generation, equivalent to 39 percent of the nation’s electricity sales.

This current estimate is significantly greater than that of a previous NREL analysis, which estimated 664 GW of installed capacity and 800 TWh of annual energy generation. Analysts attribute the new findings to increases in module power density, improved estimation of building suitability, higher estimates of the total number of buildings and improvements in PV performance simulation tools.

To calculate these estimates, NREL analysts used LiDAR data, Geographic Information System methods and PV-generation modeling to calculate the suitability of rooftops for hosting PV in 128 cities nationwide-representing approximately 23 percent of U.S. buildings-and provide PV-generation results for 47 of the cities. The analysts then extrapolated these findings to the entire continental United States. The result is more accurate estimates of technical potential at the national, state and ZIP code level.

How to use tracker control systems to your advantage

Within the 128 cities studied, the researchers found that 83 percent of small buildings have a suitable location for PV installation, but only 26 percent of those buildings’ total rooftop area is suitable for development. Because of the sheer number of this class of building across the country, however, small buildings actually provide the greatest combined technical potential. Altogether, small building rooftops could accommodate up to 731 GW of PV capacity and generate 926 TWh per year of PV energy — approximately 65 percent of the country’s total rooftop technical potential. Medium and large buildings have a total installed capacity potential of 386 GW and energy generation potential of 506 TWh per year, approximately 35 percent of the total technical potential of rooftop PV.

Key in this segment is the selection of the right mounting and racking system that makes your life easier, won’t damage the roof and is overall safe from wind and weather peril. Here’s a rundown of a few such systems and how they might save you time and cost.

System Profiles: Rooftop Ballast

Ecolibrium ballast project

Ecolibrium’s EcoFoot2+ Ballasted Flat-Roof Racking System

The EcoFoot2+ takes simplicity to a new level with integrated grounding and pre-assembled universal clamps. The modular design has just three main components: 1) A molded-resin base with no sharp edges and built-in drainage channels; 2) Pre-assembled clamps for integrated bonding without washers; 3) Corrosion-resistant wind deflectors that reduce ballast.

How does it save time and cost?

The installation speed is DNV-GL rated at 13.5 modules per installer hour. The feet can be tucked, minimizing the total footprint or allowing additional ballasting. Wire management is integrated. Bases nest to fit 50 kW per pallet, which saves on shipping.

  • Material: Black, ASA-PC, UL Listed Resin
  • Weight estimate: 3 to 7 psf
  • Slope: 0 to 7 degrees
  • Tilt angles: Landscape 10 degree; Portrait 5 degree
  • Attach option: Yes
  • Certifications: UL 2703; Class A Fire Rated; SEAOC, CFD compliant; Wind tunnel tested to 150 mph
  • Warranty: 25-year

Sollega

Sollega’s FastRack FR510

If you want the fewest parts possible, the FastRack510 (FR510) by Sollega might be the answer. It is a universal one-piece ballasted mounting system compatible with all framed modules. As with all Sollega mounting systems, the FR510 is lightweight and stackable, ships efficiently and is quick and easy to stage and install. FR510s are injection molded in California from Ultramid — an advanced glass reinforced nylon developed in partnership with BASF, the world leader in polymers. Ultramid is engineered to withstand extreme weather conditions and has a 25-year warranty. Sollega offers full engineering support services with every project, including layouts, ballast and optional anchor plans.

How does it save time and cost?

The FR510 arrives on site ready to install with no assembly required (500 kW fits in a 40-ft shipping container). All module attachments are top-down and require one size tool. Built-in reference tabs ease the alignment process. Sollega also says its system’s ability to attach rail internally provides for increased load sharing, and for hybrid systems, flexibility in mechanical anchor installation.

  • Material: BASF Ultramid glass reinforced nylon
  • Weight: 4.75 lbs
  • Slope: 0 to 7 degrees
  • Tilt angles: 5 and 10 degrees
  • Attach option: Yes
  • Certifications: UL 2703 Class A Type 1, 2 modules
  • Warranty: 25-year

Dynoraxx

Dynoraxx’s Evolution FR

The Evolution FR from Dynoraxx is designed to work with all framed modules on the market without any special ordering and requires no lead times. The system is made out of fiberglass, which provides remarkable strength-to-weight ratio that is pound for pound stronger than sheet metal, steel and aluminum and is about 70 percent the weight of aluminum on a density basis, according to Dynoraxx. Fiberglass is nonreactive with any roofing material and does not corrode or rust. Its lifespan is not affected by extreme temperature fluctuations, salty or humid air, sun, wind, acid rain and heavy snow. The use of fiberglass reinforced thermosetting resin builds structural strength directly into the Evolution. To improve part performance specific to the Evolution, the glass reinforcement is aligned along the stress points of the basket for added rigidity and support.

How does it save time and cost?

Part count is low and lightweight, which helps with shipping, and the lack of nuts or bolts means no tools are required for setup. The system comes with integrated DynoBond Grounding.

      • Material: UV-resistant fiberglass
      • Weight estimate: ~5 psf
      • Slope: 0 to 5 degree pitch
      • Tilt angles: Fixed 10-degree tilt
      • Attach option: Yes
      • Certifications: UL 2703
      • Warranty: 10-year

Kanzo

Kanzo’s K1250 Solar Racking

The Kanzo K1250 is made out of a high performance terpolymer, PC-XUV (Polycarbonate with Extreme Ultraviolet Stabilization), which has an excellent balance of UV stability and property retention. This material is designed for use in outdoor and high heat applications. It maintains an “F1” rating per UL 746C for outdoor suitability. In addition to these weatherability attributes, it has terrific impact resistance and rigidity. Kanzo says the material has a high level of chemical resistance compared to other styrenics.

How does it save time and cost?

The perfect 90 degree area allows you to measure your first row, and that’s it. The rest of the system will build out from there without measuring. The clamp provides integrated grounding and comes fully assembled, so there are no bolts or nuts or screws to worry about losing or putting together. The system is capable of 18.656-in., row-to-row spacing.

  • Material:  PC-XUV
  • Weight estimate: 3 to 7 psf
  • Slope: 0 to 7 degrees
  • Tilt angles: 12.5 degree
  • Attach option: Yes
  • Certifications: ASCE 7-10 and ASCE 7-05 Wind Tunnel Testing; ETL UL 467 Grounding and Bonding Equipment; ETL UL 2703; ANSI / ETL UL 1703 Class A Fire Rated with Type 1 modules.
  • Warranty: 15-year

 

 

— Solar Builder magazine

Wire management: What to look for when planning, purchasing your next solar system

Snake Tray's Cable Conveyance System

Snake Tray has developed a cable conveyance system that maintains a specific separation between cables that eliminates the need for upsizing cable gauges due to the derating cable because of bundling or piping.

Wires are good for two things: 1) Installing a kick-ass PV system 2) Tripping people up. To accomplish the first, you must avoid the second at all costs, which means implementing a sound wire management plan on projects of all sizes.

Planning

Just like the rest of the system, planning is important for both saving time and money. Tom Marsden and Vince Giglio from Heyco recommend laying out the cable routing on paper first before installing the solar cables. This will help you decide the best way to route the cables and what will be the most efficient use of cable mounting hardware.

Part of planning is of course purchasing, and knowing the most efficient ways to use what you’ve got.

“One way of saving time on installs would be to use stainless steel clips at the module level because you can install multiple clips in the same amount of time you can install a single zip tie, thus saving on labor costs,” says Vincent Marino, product manager for Nine Fasteners. “Also, when using micoinverters or optimizers connected to the panels, they can be applied prior to bringing the panel onto the roof.”

Nine Fasteners’ DCS-1307 Clip

Nine Fasteners’ DCS-1307 is its most popular clip. Constructed of stainless steel, it incorporates a rolled outer edge for maximum wire protection and is UL Certified. Its simplicity makes it cost competitive while still being manufactured in the United States.

Oh, and one trend to note while planning — pest management systems are starting to be required in rooftop installations, according to Marsden.

In a ground-mount, Roger Jette, president of Snake Tray, recommends keeping your power cables above ground when possible to remove the need to trench or thread cables through pipe.

“Besides being labor intensive, there is a potential of derating the current capacity of the cable,” Jette says. “With voltages now approaching 2,000 V, there is a high potential for problems if not enough attention is spent on the proper cable conveyance. Without a good cable conveyance plan, there is a potential for degradation of the cable insulation leading to arc failure.”

Let’s Get Wired: Five new wire management solutions to watch

We’ve heard plenty of horror stories from installers and manufacturers in regard to incorrect installation approaches or accidental errors, but the anecdotes that stand out most are those caused by wire management. Just seems silly to risk the performance of a $13,000 system by skimping out and choosing ties known to fail or clips known to dig into wires and cut them over time — the solar equivalent of losing a football game because of a missed extra point.

“Too many installers are sacrificing quality for costs. We have seen a number of installations

Heyco’s SunRunner Vidrio

Heyco’s latest clip, the SunRunner Vidrio, is intended for installation directly onto the solar module with compression force only. The SunRunner Vidrio is a stainless steel clip with a special TPE so it will not harm the glass surface and can accommodate glass panels from 0.13-in. to 0.25-in. thick.

where UV nylon cable ties are breaking, only to be replaced with more UV nylon cable ties,” Marsden says. “This scenario is no different than buying something for your home. Are you going to buy an appliance that needs to be replaced every two to three years or are you willing to spend a little more up front, knowing your product is backed by a warranty?” He points to stainless steel cable ties as a less risky solution.

Your other purchasing decisions dictate what wiring will need to be done as well, especially with those installing rail-less systems. The lack of a rail changes your wire management options.

“As a New Jersey installer, many jurisdictions require wiring inspections to verify that rails have been properly grounded,” says Chris Torre, installation manager at Green Sun Energy Systems, which has been using Quick Mount PV’s rail-free system, Quick Rack. “We’ve been able to eliminate the cost of the second truck roll to the site, saving an average of $300 to $400 per project. The system has integrated grounding pins located on the panel clamps, so the system can’t be grounded until the panels are installed. With this system, we’ve been able to install as many as 68 panels in a single day with a three-man crew.”

Chris Crowell is the managing editor of Solar Builder.

— Solar Builder magazine

How to use tracker control systems to your advantage

In the December 2016 Solar Builder, I discussed the industry evolution from passive to active and dynamic systems. Here’s a primer on control systems and how to make them work for your project.

The Basics

sunlink distributed tracker

Clients frequently ask how trackers will respond to a given condition. Your tracker manufacturer will have a Control Narrative that documents how the system behaves, but strategies include:

  • Excessive Wind. Trackers move to wind stow. Several manufacturers adopt a high-angle stow to mitigate torque. SunLink adopts a low angle stow and activates Dynamic Stabilization.
  • Snow. Trackers move to maximum tilt to shed snow. The higher the tilt, the more snow is shed. For example snow load is reduced by >80% at 60 degrees tilt.
  • Flood. Trackers move to flat to keep modules and wiring out of the water.
  • Obstructions. An abnormal rise in current triggers a fault that stops movement and prevents damage to the tracker.

Along the same lines, clients also ask how the control system works. It varies from system to system but generally there are several layers of communication and intelligence.

The fundamental tracker tilt behavior is governed by the tracker controller at each tracker. Data from individual trackers are sent through the communication network to the plant controller. The plant controller synthesizes data from the trackers and meteorological sensors and makes site-wide decisions about stow and manual control.

From there the data is sent to the local SCADA / DAS system or cloud for use in remote monitoring systems. SunLink’s VERTEX platform helps stakeholders track system performance by displaying critical data in a secure web app.

Impact on Economics

Given the significant role tracker control systems play in the operation of your project, be sure to take the time to discuss monitoring and control systems with your mounting system provider as part of your technology evaluation process.

This diligence is particularly helpful when it comes to commercial and small utility projects. Most developers in this segment opt to monitor performance with simple and relatively inexpensive energy meters. Energy data from the project or a portfolio of projects is accessed through a third-party data monitoring system. While that approach is fine when the system is operating well, it is insufficient for answering questions about why performance varies over time. Are the inverters underperforming? Has it been cloudy? Do trackers need service?

Spread the Wealth: We look at the value decentralized tracker systems bring to a project

A more sophisticated monitoring system could generate more granular data but would cost tens of thousands of dollars. And once implemented, the data is only as good as the insights and actionable information it generates. Too many small developers we talk to are frustrated by a sea of nuisance alarms generated by the data monitoring system and limited O&M resources to do anything about it. After all the effort to put in advanced data monitoring system, the data is ignored. For those reasons, most developers in this segment don’t use sophisticated systems.

Is there a middle ground? Leveraging the intelligence of the tracker system is one way. The same data needed to drive the intelligent control systems of active and dynamic tracker systems can complement energy measurements to answer questions about how the site is performing. Some companies are going a step further. SunLink’s VERTEX platform, for example, is designed to summarize the most important performance metrics and alerts.

Patrick KeelinThe Takeaway

Control systems and their ability to gather data and make it actionable play a pivotal role in ensuring tracker projects perform optimally over the long term. Particularly for the commercial and small utility segment, the ability to leverage real-time project intelligence collected by smarter mounting systems is essential in increasing the value of solar projects without increasing capital cost.

Patrick Keelin is Director of Product Management at SunLink.

— Solar Builder magazine

Mounting Pressure: Today’s large-scale PV boom demands new levels of service from racking companies

Solar FlexRack

For the first time ever, in 2016, U.S. solar ranked as the No. 1 source of new electric generating capacity additions on an annual basis. In total, solar accounted for 39 percent of new capacity additions across all fuel types, and these big numbers are coming via big installs as the utility-scale segment grew 145 percent from 2015.

“In a banner year for U.S. solar, a record 22 states each added more than 100 MW,” says Cory Honeyman, GTM Research’s associate director of U.S. solar research. “While U.S. solar grew across all segments, what stands out is the double-digit gigawatt boom in utility-scale solar, primarily due to solar’s cost competitiveness with natural gas alternatives.”

The trend shows no signs of reversing, and as utility-scale solar projects continue to boom, the industry demand for material and logistical services will keep increasing pressure on suppliers like never before.

Raw materials bottleneck

“It’s a simple matter of supply and demand,” says Chuck Galbreath, VP of supply chain at SunLink. “If I have more time, I can find more options and drive down costs. When schedules are compressed and I’m forced into a tight delivery window, I have to go with the supplier who is able to deliver in the time allotted, which allows less room for negotiation.”

Others agree: “We often encounter requests for expedited finished product that can be more aggressive than the lead times from the steel mills. For our proprietary racking systems, OMCO is now maintaining a responsible level of steel inventory to support these instances,” states Todd Owen, General Manager of OMCO Solar.

The time pinch has led to more in-house manufacturing. “The top five racking manufacturers have reached economies of scale where additional volume no longer decreases price, forcing manufacturers to vertically integrate by producing more parts and material in-house,” says Paul Benvie, VP of engineering at TerraSmart.

Because the sector is so dependent upon the steel market, finished product pricing can be volatile. The recent anti-dumping lawsuits spurred market increases that were felt in all steel industries, including solar. Benvie says TerraSmart has countered the pricing roller coaster by making strategic hedge buys and leaning on suppliers to honor and hold pricing so they are capable of manufacturing product at a reliable price point.

To help combat delivery delays, more mounting companies also are establishing regional centers. “Steel delivered to and from opposite coasts can have a significant impact on costs and schedules,” Benvie says. “Strategic manufacturers have set up facilities that are centrally located and/or have different branches at opposite ends of the country. For example, TerraSmart has opened a new manufacturing facility in Columbus, Ohio, and can manufacture identical parts out of the Southeast, Southwest and New England.”

RELATED: We look at the value decentralized tracker systems bring to a project 

Timelines keep shrinking

“As the solar industry matures and adopts the more typical rigid large-scale construction approach to project schedules, timelines have been compressed and suppliers are now expected to adhere to strict, tight daily schedules,” says Nick Troia, VP of corporate quality and project management at SunLink. “It is a more professional atmosphere that in some cases is straining the less sophisticated suppliers.”

The compression is substantial: “We ask customers for a 12-week lead time, but in this market we are lucky if we get eight,” says Larry Reeves, a project manager for Array Technologies Inc. (ATI). “Schedules are crazy now.”

Seasonal variations also intensify weather constraints. “The solar industry is challenging, as many financiers, developers and EPCs push to close projects out in Q4,” Benvie says. “In New England, this can be increasingly challenging with projects kicking off as the daylight hours get shorter, temperatures drop and field conditions deteriorate.”

“Without getting into the dollars and cents, delays can be very costly, such as the triggering of liquidated damages that could accumulate at thousands of dollars per day or by hindering project completion for a tax credit deadline,” observes Troia.

Losses can be the cost of customer maintenance, too. In some of these unavoidable situations, someone involved in the project has to recognize and proactively eliminate a delay before it happens.

“We believe we are truly partners with our clients, so we commonly shoulder costs or increase productivity to minimize the sting of a delay, regardless of who caused it,” Benvie says.

Next, we look at the turnkey services and systems designed for saving time on project development.

— Solar Builder magazine

Winning the Midwest: We look at how a new solar market is forming in the Midwest

Solar in the Midwest Map

You’ve probably heard, but more solar is being installed than ever before. As the cost of solar dropped the last decade, the economic case in areas of the country with high electricity prices was simple. This isn’t the case in the Midwest, where energy costs are lower, which keeps everyone mellower about the fossil fuels being mined and fracked in their backyards (we say this lovingly as Ohioans).

So, sure, most of the action is on the coasts, but even the Midwest is now starting to emerge from its cave, rub the soot from its eyes and see (and harness) the light.

Here’s what solar industry onlookers are buzzing about in the Heartland.

This article appears in the May/June issue of Solar Builder magazine. Subscribe here for FREE.

Midwest Means MW-scale

Cheaper electricity and a less demanding public means the case for solar in the Midwest mostly starts with policy incentives, and with little public demand for action, the balance of political influence over the shape of those incentives is tipped a bit more to utilities and any other interested stake holders (legacy fossil fuel companies?).

Utility-scale projects represent a little over half of the installations to date in those Midwestern states and about three quarters of the 2016 installations, according to data sent our way by GTM Research. The distributed generation markets in each state are all quite small still — sub 10 MW per state in each of the residential and non-residential markets for all of 2016.

The latest legislative triumphs in the region all seem to support this trend too with renewable energy portfolio standards (RPS) being raised in Illinois and Michigan and unfrozen in Ohio (for now). The Illinois bill in particular was two years in the making and has solar developers excited.

“It creates an adjustable block schedule similar to the successful California Solar Initiative model,” says Owen Goldstrom from Alta Energy, an analytics and procurement company that identifies and executes opportunities for renewable energy. “It’s an opportunity that we are closely tracking, and communicating to our customers with property in Illinois.”

Emerging Opportunities

chicago illinois solar

RPS standards don’t necessarily directly translate to DG solar projects unless there is a way for a smaller scale distributed system to benefit from the renewable energy credits (RECs), Goldstrom says. So, it is worth noting that these RPS bills did come with DG benefits too. The legislation in Michigan helped preserve net metering rules going forward, and GTM Research’s Allison Mond says they are classifying Illinois as an “emerging residential market.”

“The Future Energy Jobs Bill passed in the state mandates that a quarter of the 675 MW of DG required for the new RPS standard consists of sub-10-kW systems,” she says. “Though the market is still quite small, we expect residential installations in the state to double in 2017 over 2016 capacity and then continue to grow by between 100 and 200 percent each year through 2021.”

Illinois also allows for third-party ownership (leases or PPAs) of systems.

Implementation of Illinois’ RPS bill is the top issue of SEIA’s Midwest Committee, which has been working with the Illinois Power Authority to “get the regulatory language that allows the intent of the bill to move forward,” says Sean Gallagher, VP of state affairs for SEIA.

Perhaps the biggest exception to all of our Midwest generalizing so far is in Minnesota, where community solar has grown to become the third largest community solar market in the country after California and Massachusetts.

“It went from a cute idea to big business in two years, and now community solar is really picking up,” says Jake Rozmaryn, CEO of Eco Branding, the agency that represents the Midwest Solar Expo, now in its fifth year. “Large-scale development in Minnesota was over 300 MW in 2016 and is expected to be over a 1 GW in five years. Traction is there.”

midwest-solar-installations-chart

Lingering Problems

We start in Indiana, which is ground zero for problematic energy legislation right now. The much-discussed SB 309 would phase out net metering in tiers: Early adopters would be able to keep net metering for 30 years; those who install between July 1 and 2022 can keep it for 15 years. Anyone installing after that date would be under the new rules.

What are the proposed new rules? Essentially it would be a “buy all, sell all” arrangement where solar customers sell their power back to grid for the wholesale rate (~3 cents per kWh), and then buy it back at the retail rate (11 cents per kWh).

The carrot in the bill for the solar industry is that power purchase agreements (PPAs) would be made legal.

UPDATE: That bill is no longer proposed — the Governor signed it into law.

Gallagher also pointed to Iowa, which doesn’t have a huge rooftop market yet, but has an important DG proceeding happening that will set rate terms and compensation structure going forward “and perhaps set some precedent in the Midwest.”

“We’re also paying attention to a bill in Missouri that would be harmful to rooftop solar,” he says. “We’re just trying to keep those markets open. It’s not a giant market, but we don’t want to see bills that just squash it.”

Arguably worse than the specific inhibitory policies is the general uncertainty lingering over much of the region. For example, we chatted with a developer based in New York who has been eyeing Ohio as a next great opportunity. Well, with the state passing a bill to freeze its RPS, which the governor vetoed, only to have a new, even more limiting bill be passed — how can anyone get a feel for how to proceed over the long term?

Political Will of the Midwest

Getting to this point was definitely not easy, and maturing the market from here will require even more work. Relaxed Trump-era carbon regulations might defibrillate the fossil fuel industries. Longer-term environmental and social arguments in general seem to carry far less weight than short-term costs, politically. Plus, Midwestern utilities have had the benefit of seeing net metered residential systems deployed on a large scale on the coasts, and some are trying to nip it on the bud. For example, ComEd tried to get a demand charge put into that aforementioned bill in Illinois, even though the net meter market in the state at the time was around 800 total customers. The Public Utilities Commission in Ohio is also considering proposals by several utilities in the state to double fixed rates for all customers.

But despite it all, the momentum is real. SEIA and the Environmental Law and Policy Center (ELPC) formed a Midwest coalition about two years ago thinking there were opportunities on the horizon for new markets to develop. It was a baby step. SEIA took a larger step this year and formed a Midwest Solar Committee.

“We recognized that there’s been some activity toward the end of last year that’s starting to bring those potential new markets forward, which provides justification for SEIA and its members to devote more attention to those states,” Gallagher says.

“Utilities in the Midwest have a lot of political clout,” Goldstrom says. “However, solar companies and industry organization have demonstrated a significant capacity to drive change and work with legislators on policy relating to both utility scale and distributed scale generation. I have been pleasantly surprised by the success of a lot of these lobbying efforts.”

By the way, ComEd’s demand charge request didn’t make it into the final version of the bill.

“I think the biggest success solar has had in the Midwest is becoming a competitive form of generation, and as solar prices continue to come down, the cost for electricity in general continues to go up, even in the Midwest,” says TJ Kanczuzewski, president of Inovateus Solar, based in South Bend, Ind. “Even in places that have some cheaper electricity from coal or hydro or even nuclear, electricity prices continue to rise by an average of 5 percent annually while solar continues to become more cost competitive.”

Residential Solar IllustrationROOM FOR Residential

As we wrote about the lagging prospects of residential rooftop solar in the Midwest, Sunrun became the first large national residential rooftop solar company to expand into the Midwest, setting up shop in Wisconsin.

Customers in Wisconsin can either own their system outright with Sunrun BrightBuy or own and finance it with Sunrun BrightAdvantage, using a loan arranged by Sunrun.

“We see a demand for solar that has been underserved in the state and look forward to giving residents a choice to reduce their electric bills with solar, while providing value to the grid,” said Lynn Jurich, CEO of Sunrun.

This highlights Sunrun’s ability to enter new markets in a low fixed-cost way through collaborating with local partners in the state. Sunrun’s economic investment is adding job opportunities in Wisconsin, and it is currently hiring for several positions for its solar team in Southeast Wisconsin.

Chris Crowell is managing editor of Solar Builder.

— Solar Builder magazine