Category Archives: Cool Technology

Ballasted Solar PV Mounting System for Flat Roof – Part II

We have finished our ballasted roof project from earlier this summer.
(This is continuation of Ballasted Part I.)

Before getting too far along, we realized we needed to replace the building paper with Colbond Enkadrain mat  that allows the roof to drain under the entire racking system.  Roofer Stan Howard specked this product, and this is the proper way to do any ballasted system.  In this picture, the guys are using a table saw to cut this stuff – funny – sometimes you need to pull a MacGyver move on the job.

In this scenario we made sure to request information from UNI-Rac on how to attach the Enphase M-215 microinverters to the Unirac G10 rapidrac ballasted racking and attached them as specified to the brackets.  From now on we will use WEEBs to bond the Enphase microinverters to our racking saving a lot of 6 gauge copper bonding wire.

Overall our team liked the rapidrac system and it went together surprisingly quickly.  Hopefully we will have a chance to install it on a future job before the river rock ballast is put down. Learning Moment: having to manage existing rock is a large portion of the job.

This system is (4) separate arrays of 9 modules combined on the roof producing up to 8.4 amps at 240 volts AC each for a total of 8.1 kW AC.  The system size is 8.64 kw – (36) 240 watt modules.  The owner will need to install his internet service before we are able to monitor the system online.  The system has already passed inspection and the Net Meter Agreement is signed and in the line up for having it installed.  It should be activated when the net meter is installed so they can use the electricity produced from the array while they are finishing construction on the home.

Ballasted Solar PV Mounting System for Flat Roof – Part I

SBS Solar is very excited to begin installation this week on what is one of our largest residential solar systems, to date.  Most of our customers go with a 2kW-4kW system.  This one is a whopping 8.6kW – that is 36-panels at 240w per panel.

 

A ballasted solar PV mount is a graceful, highly engineered solution that secures the array without damaging the flat roof. It is compatible with the usual framed photovoltaic modules and typically does not require roof penetrations. Made from lightweight and strong aluminum construction, this Uni-rack Rapid Rack G-10 system is at a 10-degree tilt and will look pretty sweet when it’s done.

 

Right now our team is setting up the base of the system, which includes the ballast block trays which each have a 4″x8″x16″, 26-pound cement  block in each tray.  There are 5.5 blocks per panel, to keep it properly weighted down.

 

In these photos you can see the 30# strips of 36″ wide tar paper below the blocks, trays, and ballast frames.  You’ll notice that there are rocks on the roof.  This is to protect the EDPM membrane.

 

In our next post, we’ll start to show the racking and panel installation.  In the final post, expect pictures of the finished system.

 

 

SBS Solar Customer Testimonial for MT Audubon

What follows is a great Q&A with a recent install for Bert Lindler and Kristi DuBois:

1.  Why did you decide to install solar panels?

When we first bought our home, we realized that the south-facing roof offered an opportunity for solar photovoltaic panels and solar hot water.  We want to minimize our environmental impact and installing solar panels is one of the easiest ways to do so.

Kristi feels strongly that every south-facing roof is wasted space that should be generating electricity.  Industrial forms of “green” energy like commercial wind and solar farms impact a lot of habitat for wildlife, or in the case of solar farms, replace the habitat completely with solar panels.  Rooftop solar units have no effect on natural habitat, so they are a much greener way to meet our energy needs than industrial energy facilities.

We were considering refinancing our home to take advantage of low-interest rates at about the time we were reminded of the subsidies available for installing solar photovoltaic panels.  Once we had the roof evaluated for solar power potential and had received a bid for the installation (along with an estimate of the subsidies), we knew we wanted panels.

DuBois Home - Solar PV - Sprin 2012

8-panel, 2kW Solar PV system

2.  Did you encounter any challenges during the installation process?

The first challenge for us was approval from the homeowners association for our installation. Our installer prepared drawings showing the appearance of the eight panels mounted on our roof. We took to the drawings to our immediate neighbors and discussed our plans. All but one of the neighbors were supportive and the remaining neighbor said that while he didn’t want to look at solar panels on our roof, he understood why we wished to install them and would respect whatever decision the homeowners association reached. The association’s architectural review board approved our request.

The next challenge was a couple of tall non-native trees growing in our yard. We were considering having them removed anyway, but did so promptly after we learned that they would shade the panels. We still have some shading in winter from our aspen trees, but the effects on our power production are minimal. We left the trunk of one of the trees standing as a wildlife snag.

3. How long will it take for your system to pay for itself?

If the price of electricity stays in the range of 10 cents per kilowatt-hour and our photovoltaic system produces 2,289 kilowatt-hours of electricity each year as estimated, the system should pay for our cost of installation in 15 years (the system has a 25-year warranty).  If the price of electricity goes up, the recovery period may be much shorter. If the price of electricity goes down, we may never recover the cost of installation.

Our cost was much less than the system’s total cost of $12,629. We received a subsidy of $6,000 from Northwestern Energy for our 2-kilowatt installation and federal (almost S2,000) and state income tax refunds ($1,000).

Our system includes microinverters that  convert the DC electricity produced at each panel to AC electricity we can use in our home or return to the grid for use by other Northwestern Energy customers. The microinverters reduce the risk that more than one panel will be affected by shading and are provide real-time monitoring of the power being produced by each panel.

Our account is credited if we produce more electricity than we use (only likely during the summer). This arrangement allows us to receive full benefit of all the power we produce without requiring us to buy a bank of batteries to store power.

We do expect that our home will be easier to sell and may command a higher price because of the panels.

4.  How do you see your solar panels contributing/fitting into the larger Missoula effort against climate change?

Our purchase reflects our personal values, greatly influenced by subsidies offered by the power company and federal and state governments. Even though Missoula’s solar energy potential is not as high as in areas with more sun, our community could reduce our environmental impact if more of us took advantage of the subsidies that turn roofs into power plants.

What sort of lessons has the process of installing your own solar panels taught you?

Snow melts quickly off our south-facing roof. We had expected the snow to melt just as quickly off the panels. It doesn’t. The panels, mounted an inch or so above the roof, have cold air beneath them.

We use a pole-mounted plastic snow rake to clear snow from the panels and onto our deck.  The deck never used to get shoveled, but it does now.

In general, we were extremely lucky. The cost of solar panels has dropped dramatically in recent years and the cost is still dropping. The installer handled the $6,000 reimbursement from Northwestern Energy so we didn’t have to pay that cost up front. The remaining up-front costs weren’t a problem because we refinanced our home loan when interest rates were at record lows.

The panels were installed on schedule at the agreed-upon cost.  Within a week after our panels were operating, Northwestern Energy installed the special meter that gives us credit for the electricity we produce.

During December, our solar panels produced just 18 percent of the electricity we used, but as the days became longer, the panels produced 30 percent of the electricity we used during January and 43 percent during February.

We enjoy having the panels and we’re happy to see them producing more electricity as the days keep getting longer.

Bert Lindler and Kristi DuBois

Energy “Smart Home” a Reality with Passive House

The Cleveland Museum of Natural History has a remarkable new exhibit.   Coined the future of green building technology, the museum has sponsored a “smart home” that has been designed to meet Passive House standards and will seek Passive House certification when placed in it’s permanent location.

The museum had over a hundred partners participate in the design, build, financing and furnishing of the home and garden that is now open to the public to tour on the museum campus.  As typical to Passive House specifications it is extremely air tight, super insulated, contains no thermal bridges, and does not need a conventional furnace.  The home instead is heated and cooled with a small ductless air source heat pump.

Though the home was not seeking well known LEED certification, it was designed with LEED  criteria in mind and has many features that address the overall environmental impact of the building, besides energy usage.  It is also seeking “Green Communities” certification which was developed by Enterprise Community Partners, a national funder of neighborhood redevelopment.

Alexander (Zandy) Sievers, SBS Project Technician
RESNET Home Energy Rater
NorthWest Energy Star Homes Verifier
NAHB Green Building Verifier
T/(406)396-2661, zsievers@sbslink.com

SBS Summer Reading Heating Up: Solar? Conservation? Efficiency

While there certainly has been a lot of talk lately about the weather, and whether global warming is real or not, the concept of climate change is certainly on our minds (or should be).  It seems that catastrophic weather events are more prevalent than ever: from tornadoes to floods to tsunamis, earthquakes, mudslides and volcanic eruptions.

In response to these major weather events, and in an effort to gain some knowledge, I have been doing some summer reading.

First on the list is a behemoth of a book – and worth the hundreds of pages – Hot, Flat and Crowded by Thomas Friedman. Simply put: We are getting hotter as a globe from fossil fuel energy dependence.  We are getting flatter as a world through wireless technology.  We are getting more crowded as a world through population growth. This book points out, more than ever, the mounting global energy crisis with the advent of a larger-than-life working-class in major cities around the world,  namely China and India.  It also details some very viable ways we could remedy the current situation and prevent total global melt-down – like applying the idea of a smart grid to our utility use and billing, efficiency and renewable now (not later), government mandates and crackdown for laziness in getting on board, and even suggesting that the USA needs to getting into a race w/ China to “out green” one another – akin to the space race with former USSR that put a man on the moon in short order.

Another great read, and a bit shorter, is an  article in Rolling Stones:  “Al Gore: Climate of Denial: Can science and the truth withstand the merchants of poison?”  This article addresses the question of whether we are all in denial about climate change or not.  Former Vice-President Al Gore emphatically says “Yes, we are in denial.”  The final paragraph states:

The climate crisis, in reality, is a struggle for the soul of America. It is about whether or not we are still capable — given the ill health of our democracy and the current dominance of wealth over reason — of perceiving important and complex realities clearly enough to promote and protect the sustainable well-being of the many. What hangs in the balance is the future of civilization as we know it.

And finally, the shortest of all the reads, an article from Newsweek: “It’s still the Economy, Stupid. 14 Ways to put America back to Work” by 42nd President Bill Clinton. In June 2011 in Chicago, the Clinton Global Initiative (CGI) focused on America for the first time, inviting business and political leaders to make specific commitments in support of the former president’s jobs blueprint, which he details in this article. Here Clinton outlines his plans for economic stimulation.  Interestingly enough, the first half circled around energy efficiency and the funding there of.  Namely, #2 Cash for Startups, #3 Jobs Galore in Energy, #4 Copy the Empire State Building, #5 Get the Utilities in on the Action, #6 State-by-State Solutions, and #8 Paint ‘Em White.  And, really, all fourteen talk about energy conservation relating to economic stimulus in one way or another.

So sit back, try to relax and enjoy the reading.  (Then change out all your light bulbs to CFLs and LEDs, install a solar array and fix that leaky faucet.)

Solar Prices drop up to 25%!

After a PV module industry wide cost reduction, sourcing a lower cost mount system and dealers giving better pricing on all balance of system components, SBS has new numbers for potential Solar PV customers in MT that represent up to a 25% reduction in installed costs for PV systems!

If you couple the new lower prices with a $6000 Northwestern Energy PV grant, the 30% Federal Tax credit for renewable energy and the $500/$1000 (single/couple) State Tax credit, the costs are lower than every before.

And here in Montana, we can add to that a 10-year, 4% financing option (oac) from the MT DEQ revolving loan fund for renewable energy.

For a 2kw, 9 module system, total cost to the customer is in the $12,000.00 range.

After incentives this is roughly 3,200.00 out of pocket.

This on average powers about 25-40% of the average Montana home.

Here is an example of plausible breakdown for that $12,000 system

$12,000 GROSS
– $1000 (deposit to SBS to begin work)
=$11,000 NET
-$6,000 (NWenergy PV grant)
=$5,000 – Financed w/ MT DEQ loan
120-months
4%
=$51/month

Yes, that is correct, for at little at $51/month for a 10-year period, you can cover up to 40% of your energy bill. Awesome.  Check out this PV for more information: SolarPVFinancing-Basics-final.

And, when you file your taxes at the end of the year on that system, you’ll still get the $1800 Federal credit and the $500/$1000 state credit back.  You can keep these to use however you’d like, or put that money into your DEQ loan for early pay off (there is not penalty for early pay).

For a free solar site assessment, or to learn more, contact us at SBS today: info@sbslink.com, www.sbslink.com, 406-541-8410.

To get a general estimate of your solar or other renewable energy needs, try our Solar Calculator here.

Hamilton’s first Pole Mount Solar Array

The Moore’s of Hamilton, Montana completed installation this Fall 2010 of a 10 module photovoltaic system which will provide 40% of the electrical power used in their home.  The pole mount solar array is mounted on a tracking system which follows the sun from East to West through the day.  The electricity is run into their home where it powers any electrical appliances that are currently in use.

If more power is available from the array than can be used by the home, this excess power will then turn the electrical meter backwards creating a financial credit with the utility.  This credit can then be used at night or this winter when the power draw of the home exceeds the solar power production.  So you can see that a system can easily be designed to provide any portion of you power bill that a homeowner determines.

This PV system(short for photovoltaic’s) is one of several in downtown Hamilton that Dan Brandborg , a native Bitterrooter has been involved with since he started working with PV in the early 80’s.  He has worked with Sustainable Building Systems out of Missoula, since 2009.

Solar Highways – The Horizon is Near

Now this is something I am excited about. My mom sent me the link to this video over the weekend and she is right on. Solar Highways. If we were able to construct a save road, parking lot, highway materials w/ photovoltaics under super strong glass we could harness enough energy to cover ALL USA ENERGY NEEDS PLUS 15%!!!

Let that resonate for a moment.

No oil based electricity.

No coal powered electricity.

All solar. ALL SOLAR.

They even go on to explain how post consumer waste, otherwise headed for landfills, would be the source, mixed with other organic materials, to form the base and structure for the panels.

And finally, from a safety perspective, they plan to include embedded LED lights, powered by the solar, that would be used for a myriad of reason like lighting up crosswalks, giving messages like “SLOW DOWN, CONSTRUCTION AHEAD,” changes in speed limit, etc…

Watch the entire video here.

As I was noodling around in related news, I came across another neat happening in the past year. The State of Oregon is putting together some of the first highway solar projects along the highway like the arrays along the autobahn in Germany.

You can view that video here.

Renewable White House: Solar in DC!

In a post by the Council on Environmental Quality on the White House website, it was announced today that the President “plans to install solar panels and a solar hot water heater on the roof of the White House Residence, a project that demonstrates American solar technologies are available, reliable, and ready for installation in homes throughout the country.”

Please take a moment to read the entire post here.