Solar Women Summer Series: Commercial Project Design and Engineering

• Receiving NABCEP certification is more important than ever, with utilities and Authority Having Jurisdictions (AHJ’s) now requiring the certification as a pre-requisite to licensing and incentives.
• With financial considerations being one of the biggest barriers to solar implementation, and because solar is a totally front-loaded investment, (with future returns over time) long-term production estimating is critical.
• When PV modeling, utilize resources like Helioscope, PVWATTS, PVSYST, SAM (System Advisor Model), and Sketchup, for greater industry understanding read Home Power and Solar Professional magazines, for networking opportunities attend Solar Power International and join WiSE!

Tell us more about you! What do you do? How’d you get into the solar industry? What did you want to be when you “grew up” (age 5-10) and is that at all related to what you do now? 

I was an only child, and was taken constantly to the library by my Mom from an early age. I read EVERYTHING I could get my hands on. Loved science, technology, history, mysteries (especially Sherlock Holmes and old private eye novels) and science fiction. I wound up running several SF conventions. Total Nerd.

Although a City kid, I spent every summer working on my Grandparents rural commercial farm, where if you were there you worked. Learned to drive on trucks and tractors. Learned to do stuff. Ended up going to school in Florida with a degree in Ocean Engineering (heavy on civil and mechanical engineering courses).  Engineering internships at two companies were a study in contrasts, in one I was doing design work on a floating offshore oil supertanker port, and the other helping design parts for an open-ocean oil spill recovery skimmer! (All this before the Exxon Valdez spill in 1985, or the BP Gulf spill… we never learn, do we?) I‘m showing my age here. 

But job options were limited if you weren’t part of the “Boys Club”, so I worked for a while as a field and sales application engineer for a company that made earthquake monitoring and telemetry equipment (seismographs.) They had an early PDP-11 based system for instant detection of earthquake epicenters from a seismic telemetry network. Some of those remote stations were solar and battery powered.

Also had a stint as an industrial fire and loss prevention engineer which exposed me to many different types of industrial and manufacturing technologies and systems.

I shifted into the microcomputer industry early on (my first PC ran CP/M!), did software and hardware marketing and sales and ended up in the high-end graphic arts industry doing electronic pre-press and LAN support, I was also a pretty darn good typographer and graphic designer.

When economic conditions hit the printing industry pretty hard, I followed up on my interest and love of historic homes and architecture ( I live in house built in 1911) and went into Real Estate for a number of years ( I know, left field shift here!)  (RE/MAX and others, a specialist in historic homes). As an old Earth Day kid (the first one), I hopped on the Green Building bandwagon early, and focused on energy-efficient homes and retrofitting historic homes (a big challenge).

While I did well as an agent, my bent and love is obviously more technology oriented, so when the real estate market tanked, I went and got certified as a BPI (Building Performance Institute) Building Analyst and Envelope Professional. I also got myself into an early Solar Installer training program designed to prepare you for the NABCEP Entry Level Exam. Energy Efficiency was fun, but Solar became my passion. We are obviously now on the path of totally rebuilding our energy infrastructure and it is exciting.

What is the Vote Solar Project? Do you think there will be more projects like it in the future? How’d you get involved? 

Vote Solar and World Wildlife Fund provided grants towards a discounted group buy for residential solar installations in the City of Chicago. My company, Microgrid Energy, was a main winning bidder and I was the primary designer assigned to the program. A high percentage of folks who signed up came from older, historic parts of Chicago, in very built up areas with older homes and trees, flat roofs, steep roofs, chimneys and other things that give solar folks nightmares. Plus, there were multiple Authority Having Jurisdictions (AHJ’s) and fire codes and roof offsets to deal with.

Initial site surveys revealed many old and varied electrical panels and services, so we made the decision to standardize on supply-side landings, which was not something that familiar to the AHJ’s, but we got approval and it avoided a morass of internal home electric service upgrades. Plus we had several pre-selected (but new to us) local subcontractors we had to interface with and supervise. It was quite a project.

Although many contacts did not follow through for financial reasons or not solar suitable homes, the initial response to the program was so overwhelming; it shows the pent-up demand that exists.

Why should someone interested in the solar industry get the NABCEP certification? Any advice or words of encouragement for someone thinking about studying for and taking the exam? When’d you get your certification?

Because it arose from such a cross-discipline history, there really isn’t a firmly established, high visibility solar-specific engineering association (Industrial, Civil, Mechanical, Electrical, and Environmental, All of The Above?) Likewise, the electrical trades were key partners in developing safe and reliable installations, and early drivers in the establishment of NABCEP.  The very high standards they enforce have become the de-facto mark of professional knowledge in Solar, whether you come to it from the engineering side or the trade side. It’s a tight partnership.

Also more and more utilities and AHJ’s are now requiring NABCEP certification as pre-requisites to licensing and incentives. The required combination of book knowledge and hands on-experience makes it a tough but prestigious certification to achieve.

Start with one of the good courses out there (Heatspring has some of the best) and study for and pass the Entry Level Exam. I personally don’t think it is “entry-level”, you have to know your stuff to pass that exam.

Your next step is gaining the experience necessary to qualify to take one of the full Certification exams. This won’t get handed to you on a platter; you will need to seek it out. Plus a good exam prep class is essential (Heatspring can help you here, too). I sat for and passed my PV Installation Professional exam in 2014.

Then you need to stay on top of things and improve yourself as technology and industry trends change, plus you need quality continuing education to maintain your certification. I hope to be able to budget to take Ryan Mayfield’s Megawatt Design class, as I am doing more and more large-scale system design work for my current employer.

What has been your favorite solar design/installation to-date? Why? 

My favorite is still my very first project, right out of a community college solar training class, where I talked my way into running a 25kW 3-phase Enphase microinverter commercial ballasted flat roof install for a developer who didn’t know quite what he had taken on. I designed it, specified all the equipment, permitted it, arranged for logistics and delivery of all items, was the on-site PM and crew boss, and did a lot of the install work myself. We passed inspection first time with flying colors. It was a bit of a cowboy operation, but the learning experience was unmatched. Now I work with a team, so don’t get to do everything anymore.

3 of your top tips for people getting into solar sales? Any trainings you’d recommend? 

If you want to sell solar, jump on getting your NABCEP Entry level ASAP, it will give you the background and knowledge you need. The NABCEP Resource guides are very useful (and free) resource. Also start with a good overview book to see if this really is for you (something like Dan Chiras’ “Power From The Sun”).

Get a good basic understanding of the astronomy of the sun and assessing a prospect site for solar potential. Shade is not your friend! There are some really cool Android solar path and compass apps that can help you with quick evaluations, and can serve as a good learning tool.

Learn how to use PVWATTS (easy) and SAM-System Advisor Model (not so easy, but also free!)

Go around to every solar sales company you can find and pester them for a job, armed with enthusiasm and knowledge. But it is still a sales job, so have some skills or experience there also will help.

Getting people or companies initially interested in solar is not hard, everyone wants out from under the thumb of the utility (you’re not selling insurance here). But you have to be skilled to present the financial benefits to such an investment, once you get down to the “numbers”.

Your go-to resources for solar?

Outside of the standard textbooks like Jim Dunlop’s, the Mike Holt guides are great for easing into the NEC (National Electric Code).

But the best resources you can get are the back and current issues of Home Power and Solar Professional magazines. That’s your “Encyclopedia Britannica” of solar.

If you are the nerdy academic type, dive into the NREL (National Renewable Energy Lab) site, EIA (Energy Information Administration), LBL (Lawrence Berkley Labs) and Sandia sites (not for everyone).

For daily industry snapshots, check out newsy websites like GTM, Renewable Energy World, Solar Industry Mag, etc.

For an intense dive, if you are nearby, consider getting a one-day pass to the exhibit hall at the annual SPI (Solar Power International) annual convention, which rotates around the country each fall.

Why’d you join WISE?

There are still just not enough women in the STEM professions, especially in renewables, which is nominally a very progressive industry. I think in general it is welcoming; we just have to get more to see it as a great career to consider. Also, my co-worker Kacie is Vice President (but that had nothing to do with it, of course) and was a speaker at the #nationWISE multi-city women in solar roundtable this last February.

What do you like to do for fun? 

My current diversions are building up/restoring vintage bicycles, and I want to build a solar powered electric trike bicycle (that will be a while..)

I have a long-time love of photography (even had a few professional side gigs) and can get lost in composing a great photo.

Currently training myself as an aerial photography quad-rotor pilot aspiring to professional level proficiency.

And to seal my solar-nerd credentials, I once built my own version of a Solar Pathfinder shade tool from bamboo and brass.

Talk to me about PV modeling – is it hard? What do you need to know to be able to model? Is it something that someone could easily pick up or do they need a particular educational background? Do you like Helioscope? Why? 

There is 3D modeling for physical design purposes, and production modeling for financial purposes.

I often have to do a preliminary design on a roof that is far away, that no-one has yet visited.

For a remote initial site assessment, I’ll first fly through the site in Google Earth Pro, if the topographical and 3D data is there, you can fly around and look for problems, like a building that is between steep hills that will reduce the solar window, or nearby tall buildings.

For challenging commercial roofs with lots of stuff on them, and/or multi-level elevation changes, if I can estimate vertical heights from Pictometry or other sources, I may build a 3D Sketchup model and use the shading slider to look at how the shade moves around on the roof to establish design boundaries. Also, it is very cool to show folks how that happens.

Everyone agrees that solar is better than coal, but when you sit down and say “Let’s Do It” the first topic is actually “Show Me The Money”. That is why long-term production estimating is so important, because solar is a totally front-loaded investment, with future returns over time, sort of like an annuity.

So you are estimating the output of a given site based on the latitude, longitude, tilt, azimuth and spacing of the modules, factoring in shade, and then historic weather records, as cloudiness, humidity, and temperature modify the available solar resource on  a given date.  Then the production over time is converted to a monetary return based on offset utility costs, investment credits, etc.

The simplest modeler is PVWATTS, and more sophisticated ones include PVSYST and SAM (System Advisor Model). They all allow you to estimate likely production over a given time interval and do financial return estimation. But you really need a preliminary design already worked up for your particular site as an input, and estimates of any shade reduction from nearby obstructions.

That’s why Helioscope has become a go-to tool. It basically gives you a 2D CAD solar layout tool on top of a geo-located google map, and allows you to quickly build realistic designs, with keep-outs for obstructions and automatic setbacks. It uses the actual characterizations of particular modules and inverters, and TMY or satellite solar resource data to give an accurate estimate of production from each module.  You can also build near-field 3D shade obstruction models in SketchUp to see the actual impact of shade on production, and they are adding more of that capability directly into the program.  While it will give you string size starting points, it won’t do all your thinking for you, I like to calculate the best string size for an inverter the old-fashioned manual way first, and setup a frame size in Helioscope that is an even multiple of that, so I end up with more accurate models. I have my own custom string design tool I created in Excel.

The latest Beta version of Helioscope which I tried is adding parametric optimizations, so you can do auto runs varying tilt angle, row spacing, and so forth to determine optimal results. You can actually do that now manually and I did an interesting set of runs on a basic ground mount array in a fixed-sized area, and built a heat-map table in Excel showing which combos gave the highest specific yield and highest annual production in that space.

They keep adding more and more features; it is becoming a standard tool. Right now it does not do the financial analysis, but does give you an 8760 production data file that can plug right into standard financial projection tools, like EnergyToolbase. The combo is very powerful.

Thank you, Shannon!

 Additional Resources:

• Learn more about women in solar via RenewableEnergyWorld.com(the exclusive media sponsor of this summer series!)
• Use our Free Solar Comparison Tool when comparing solar proposals for homeowners
• Learn more about Vote Solar and their initiatives for making solar a mainstream energy resource across the United States
• Free Course: Solar PV Design, Code, Economics, Sales and Site Visits with Chris Williams, Christopher LaForge, Ryan Mayfield
• HeatSpring Course: Solar PV Installer Bootcamp Training + NABCEP Entry Level Exam Prep with Fred Paris
• Free Tool: 2015 Solar Startup Guide by Chris Williams
• Learn the financial modeling background and perspective often lacking in deal negotiations by taking our Solar Executive MBA Training Course with Keith Cronin and Chris Lord
• Check out the National Women in Solar Initiative webcast series hosted by GRID Alternatives and SunEdison
• Free Course: How to Use Solar Leases to Grow Your Solar Business with Chris Williams
• Study with Ryan Mayfield, Solar PV Technical Editor at SolarPro, by taking Megawatt Design