Solar Installation Challenges: My First Person Report
Category: Solar Panels
Do-It-Yourselfers Need Not Fear Solar
Many installations into my solar career, my boss asked me to write a piece on "solar Installation challenges." There are a multitude of challenges facing the do-it-yourselfer (or the new installer) - but the good news is you can learn from my mistakes and install an array when the sun's shining, perhaps on a weekend? If you've done any home improvement or are familiar with the aisles at Home Depot, chances are you have the skills needed to install an array, and install it well.
Design, Design, and Design
Like a kitchen remodel, solar arrays take a bit of planning, and planning pays off. The most important decision is to make sure you've selected a good site for solar energy for your home. This seems like a no-brainer, but if you put an array up without understanding the shading obstacles at your location, you're likely to be disappointed. A SolarPathfinder is worth its weight in gold - this device will show the solar window available at a chosen site very quickly. It's amazing how humans can underestimate the height of a tree in the neighbor's yard. Some sites don't need a pathfinder - this week I was on a flat roof of a duplex next to the neighborhood soccer field and we were above everything, except the clouds that swept by in the afternoon. The main point is solar is a lot like real estate: location, location, location.
Sizing Your Solar Array
Let's say you skipped that last paragraph as you're confident the site you've chosen is ideal for an array. Great - how do I start? Now we're back to the kitchen remodel: you've got limited space to work with, so grab a pencil and write down the dimensions of your roof. A great rule of thumb is that you can get about 10 watts of power for every square foot of solar array.
You should remember, however, that similar wattage solar modules come in different sizes depending on the manufacturer. Take a look at the SolarTown article comparing some of the leading manufacturers' solar panels. As shown in that article, you may be able to get as many as 28 Canadian Solar panels on a 500 square foot root, but only 24 Sharp solar panels. But here we are only talking about a rule of thumb. So if you've got 500 square feet to work with, you can install about 5kW of power - enough to power a small home.
Racking and Panel Mounts
At this point you should know where you're going to install, and how much power you'll make. What's next? For many, it's less about the panels and more about the solar panel racks. Why? Well, every panel that SolarTown sells is already UL listed - they've been through testing and have warranties up to 25 years. Does your car have that kind of warranty? But what about the rack? If you are installing a solar ground mount or solar roof mount, the rack is what points your array at the sun and holds it there for the next 20 years, so understanding your site and understanding the rack is essential. Take a look at the solar mounts that SolarTown carries.
What's in a rack? Most manufacturers are making racks of high grade aluminum that can withstand high winds and heavy loads. If you're interested in putting an array on a 100 year old house, this is a good time to hire a structural engineer. Moreover, if the roof you're going to mount on is not a metal roof, and is over 10 years old, then the rule of thumb here is to talk to a roofer and a structural engineer. Many installers won't install on a roof that is over 10 years old, and the reason is simple - arrays need to mount into the roofing trusses and an old roof with a good bit of wear is prone to leak. Our goal as installers is to make sure owners are happy with the systems they buy, and you won't be happy with a new array if it causes a leak in your master bedroom!
Structural Engineers for Some Solar Installations
The racking and mounting systems used to support solar arrays are often overlooked - so take the time to assess the condition of your roof and verify the structure of it. Structural engineers can vary in the fees they charge - when you hire one, ask if they've done solar work before and how much it should cost. Reasonable engineers should be willing to discuss the project with you and let you know what they provide and how much it will cost before you hire them. Don't expect an exact number - I'm talking ballpark figures here. The older the building, the more the engineering will cost.
The key verifications they'll provide is that your roof is suitable to handle the weight of the array, the size lag bolts necessary, and the depth of the bolts into the roofing rafters. The solar industry has matured over the past 25 years, and racking manufacturers can provide some good information and documentation on a chosen racking system. City permit offices may not have kept up with the times - in many regions of the country a permit isn't necessary. But we're dealing with electrical and structural designs, as well as interconnection issues with your local utility. Bottom line is talking with your permit office and utility can be invaluable if you're doing this for the first time.
Setting the Feet for Your Solar Array
After validating your location, understanding the amount of power you want to produce, and verifying your structure you're in a position to make good decisions. As an installer one of the biggest challenges of the installation is setting the feet. What I mean is either positioning a pole (in the case of ground mount) or setting the feet of the rack support structure. If you're doing this yourself and have never done it before this is a good time to hire a local roofer. If you don't want to get this dirty you could hire this piece out, and it generally takes about a day for one or two people to set the feet of the rack into your roof. If you're ground mounting an array and need to set a pole, call a professional to do this for you - ditch digging is tough work and the people who do this for a living will run rings around your back breaking efforts. At the end of the day, having the pole or feet set correctly is essential, and is the most challenging aspect of installing an array. After the base is set, the array should piece together pretty easily.
Installing the Component Parts of Your Solar Energy System
Once the feet are set, and the roof is sealed, the next piece is installing the rack, running wires, and installing a solar inverter (or a micro inverter such as Enphase). These tasks can be done in a sequential manner, and it gets easier as you go along. Bending conduit and running wire inside it isn't very difficult, but if you haven't done it I'm sure you'll find the hard way to accomplish this. Good tools and installation experience should not be underestimated here, and its one reason electrician's tool boxes are so full - there are a great many tools to employ for running wire, staging conduit and connecting fixtures. Grounding should also be installed at this point, and crimping tools are necessary to bond the grounding conductor to the racking system. Again none of this is rocket science, but wiring everything before the panels are laid down is invaluable. Once the panels are exposed to light, the power is on, and you do not want to change what is underneath the solar panels-otherwise you may get an unwelcome shock.
Placing the Solar Panels
After your rack is installed, the solar panel wire is run, and junction boxes and solar AC DC disconnects are wired, the final piece are the panels themselves. Like many remodels - you'll get out what you put into it, and if you've planned the installation and staged the wires well, the solar panels will be most satisfying. They are heavy though - and unless you're working on the ground or on a flat surface you'll need one or two partners to put them in place. More important - safety harnesses are worthwhile! Solar panels typically go up fairly quickly, and you'll be used to your roof and ladder at this point.
Turn it On!: Your Solar System Comes Alive
Once they're installed you're ready to turn it on. A frustrating item at this point (particularly for the do-it-yourselfer) is you'll need to get it inspected before you can flip the switch. Inspectors can drive installers crazy, but they serve a good purpose: an objective assessment that your array is installed correctly and is safe to turn on. In my area the inspection is required before the utility will provide a net meter. Without the net meter you might produce great power, but some meters only count watts, instead of ‘net metering'. What I mean is many newer meters will spin faster once an array is turned on, unless they are a net meter!
Installing solar systems is not overwhelmingly difficult, but it does take preparation and planning. If you take the time to plan it well and install things in a sequential manner you'll be rewarded. My favorite web site after going solar is the one that shows the power I make on a daily basis! Take a look if at how my solar energy system is working in real time here. Seeing the power I'm making going back to the grid has made it all worthwhile.
Tags: Solar Panels, Solar Installations, Installing a Solar Energy System, Solar Modules, Canadian Solar Panels, Designing a Solar Array, Designing a Solar Energy System, Installing Solar Panels, Installing Solar Modules, Sizing a Solar Array, Sharp Solar Panels, Solar Racking, Solar Inverters, Solar Module Installation, Solar Energy System Installation, Racking for Solar Array, Net Meters, Panel Mounts, Structural Engineers, DIY Solar Panels, Solar Panels for Home