New User-Friendly Solar PV System Design Software Emerges from Beta

After nine months in private beta, Folsom Labs has officially decloaked with its solar PV design software that it says is as accurate but vastly more usable than the industry’s incumbent tool, claiming to cut down design times by up to 75 percent.

Folsom Labs has been quietly testing its HelioScope software since March 2013, and now has over 800 users from small mom & pop installers to some of the industry’s biggest developers with the biggest projects, though or course their intensity of usage and productivity varies. The goal is to unseat PVsyst, today’s default PV design tool deemed “bankable” in the industry, using a component-based model rather than an aggregate one.

Here’s how it works: a user selects a project (i.e. a location, built on Google Maps) and develops a design with numerous component selections (modules, inverters, wiring, racking, etc.). The system applies the scenario for weather and environmental factors, and runs simulations based off all the data to gauge system performance (MWh, kWh/kWp, and performance ratio). In a few clicks a user can clone a system design and rerun the simulations with different inverters, modules, or even wire types and lengths, and compare the results. HelioScope uses 3D-shading patterns out of Google Sketchup to generate shade modeling and analysis.

With PVsyst, users start in AutoCAD module layout then switch to its software to add variables and calculate performance projections. It’s a good design tool for providing estimates if you provide the right information and know how to use it, but it’s a complicated program with a complicated interface, explained Rebekah Hren, a solar PV designer and installer for the past decade and instructor for Solar Energy International (SEI). HelioScope, on the other hand, has a “drastically improved” UI with more intuitive features on the design side, and on the simulation side it’s easier to run multiple simulations while changing variables and comparing the results. “That’s something you can do in PVsyst but not nearly as easy,” she said. By comparison, “anyone who’s been in solar for six months knows how to use” HelioScope, Grana noted. “It doesn’t require weeks of training.”

BEW Engineering did a study of HelioScope and PVsyst, simulating two types of designs on a large U.S. Post Office roof in Phoenix, Arizona, and found their results to be within 1 percent each other, close enough for HelioScope to be considered “bankable” as well. Grana says HelioScope already has been used as the model of record on “a handful” of bank-owned projects in sizes ranging from 500 kW to around 1.5 MW.

For now the software is launching with a number of just-introduced features, based on customer feedback, to incrementally streamline the experience: “Keep-outs” and “negative spaces” to redraw arrays around obstacles like AC units and access paths; adding “frame size” criteria to restrict a layout to accommodate only certain module setups (e.g., the 3×4 array configuration of a particular ground-mount racking vendor); automatically taking real-time satellite-image screenshots of new design versions, so designers can walk others through their design decisions and modifications; and incorporating municipal construction restrictions — say, tracing out the exact building edge of a rooftop array, and then moving it back 6 feet to comply with that specific town’s building code.

Those tweaks reflect solar designers’ most immediate needs, when they actually lay out modules and components when doing an RFP, or filling out a field with a particular supplier in mind, Grana said. Automatically calculating the total modules needed in a particular array’s 3×4 patterned layout saves users from pulling out a calculator or scratch paper — a small time-saver, but those add up to make a big difference in the end.

It’s not just users who can see benefits from this graphical design approach, either. Say a designer goes to a racking company and says, ‘here’s a project I’m working on, with this design it looks like I’ll need X number of your 3×4 structures.’ The supplier can look at that report and suggest a different array sizing with a different product, quickly rerun the simulation, and perhaps show that 6 percent more modules can be fit into the same space, which changes the array’s output and economics. Note that Folsom doesn’t participate directly in that conversation — their software just makes facilitating those discussions simpler.

The next big feature upgrade will be tighter integration with AutoCAD, the format required for most permitting documents and used by on-the-ground engineers, Grana says: the ability to import imagery delineating property lines and setback areas, and also export a HelioScope design into AutoCAD to avoid individual hand-drawing of layouts. “We’re the first half of the process,” he said. “We’ll never out-CAD CAD, but we’ll be solar-specific.”

Also on the horizon is translating those performance results and comparisons into actual cost/financial modeling (LCOE, ROI, or IRR), thus completing the loop for PV system bankability. That was the thrust of Folsom’s $350,000 SunShot Incubator grant last October. That grant, which began on January 1, was pushed back by the company, actually, to get some other features of HelioScope ready. It runs through the end of this year. Most of those capabilities will be internally developed (Genability’s rate engine will be added for utility tariffs numbers). And like today’s tweaks, some additional functionality will be built in for streamlining the system design decision processes based on user feedback, Grana said.

HelioScope is being offered as software-as-a-service; data is hosted in “the cloud” (two clouds on two continents actually), free to be downloaded and exported. Pricing for a seat license is $95/month or $950/year.