Residential Solar Panels, Solar Service
Written by Lisa Walsh

Diagnosing and Preventing Critter Damage to Solar Panel Arrays

Solar Service ,Home Solar Panels It’s no secret that hundreds of thousands of homes have installed roof mounted solar panels, with that number increasing with each passing day. The upward trend brings increasing problems that arise when tech meets nature. In an acorn shell we’re talking critters who nest, feed, chew and live their critter lives in and around solar panel installations.

Which Critters?

Any animal that can fit under your array poses a risk to a solar installation. Pigeons and other birds looking for a warm/safe place to build nests may do so under a solar array. This doesn’t usually cause any malfunction to the system. However, water build-up and bird waste may cause minor roof damage and may be more of a nuisance than anything.

Squirrels, mice and rats, on the other hand, can wreak havoc on a solar system. These members of the rodent-family have teeth that require filing down throughout the course of their lifetime. The wires, plastic connectors and small parts that run underneath the panels can be excellent teeth-filing equipment. We have seen squirrels chew the outer plastic covering of wires, as well as penetrate junction boxes on the back of panels and chew into the solar panel interiors. This type of damage will cause panels and even whole systems to cease power production.

Solar Service, Home Solar Panels ,Washington DC SolarWho’s at Risk?

Any solar system can be susceptible to critter damage. However, those most at risk are usually systems that are in wooded areas; particularly where tree branches extend close to the rooftops, allowing easy access for squirrels to make the jump from branch to solar system array. Although many homes and businesses fit this description, it’s also worth mentioning that for every critter complaint we’ve had – there are 20 or 30 more systems that have had NO issues with critters. However, it’s also worth mentioning that most of our customers are no more than 10 years into a 25 – 40-year solar system lifespan. Time will tell what the probability of critter-damage risk over a system’s lifetime will end up being.

Detecting and Diagnosing the Damage

Most solar system owners first become aware of a problem when their solar system does not seem to be producing as well as it used to. For homeowners with online monitoring, they may see that a string of panels – or individual panels (in the case of those systems outfitted with a microinverters or optimizers) are no longer registering power output. Others may hear scampering around on their roofs and may notice their utility bills creeping up. That’s when they call our service department. Our technicians need to remove and inspect each panel, as well as their connecting cables, suspected of damage. In most cases, we can remediate the wire damage onsite without engaging the solar panel manufacturer for a replacement panel. Whether this takes removal of every solar panel, or just a few – depends on the extent of the damage or ability to detect the extent of the damage.

Home Solar Panels,Solar Service, InstallationInstalling Critter Guard

There are a variety of anti-small-animal solutions out there for solar systems designed to create a barrier around the perimeter of the solar system. We usually choose the one most compatible with your solar system; depending on the type of racking initially installed. Most critter guards are made of some type of strong steel-mesh screen and they do not require drilling into the roof.

One of our more popular systems, the aptly named “Critter Guard” employs clips that attach to the bottom flange of the module frame and have hooks to snap the screen into place. The clips are painted steel and can be snapped to the appropriate length to accommodate height variations so there are no small spaces that accommodate a small animal. The mesh screen is vinyl-coated steel, rigid enough to keep out even the most industrious squirrel.

Residential Solar Panels ,Solar ServiceCritter Guard is now a standard option that we offer to our customers and we strongly encourage it when the structure has trees that are encroaching on the rooftop. While the tree branches may not be close enough today to make contact with the roof, over time, if not maintained, they can grow out to become that ideal path to an appealing new nesting site.

What are the costs involved?

The costs are always less if you can prevent the problem in the first place. Adding Critter Guard at the time of installation typically costs from $500 – $2000 depending on the size of your system; but of course this cost is integral to the solar system so most tax advisors would agree that the 30% tax credit would apply.

The costs for any rodent damage remediation will depend on the extent of the damage. Critter damage is not related to defects in installation covered under our standard Workmanship Warranty; neither will most solar panel/inverter manufacturers consider this damage a Material defect. Our service department charges Hourly-Time + Materials. These costs may range anywhere from $500 to $4000 for a mid-sized solar system including all remediation and installation of Critter guard to prevent further damage. We recommend inquiring with your home’s insurance agent to see if the costs can be covered under your homeowner’s insurance policy.

Residential Solar Panels, Solar Service ,Home Solar Panels
Written by Anonymous

SES Selected as Installer for Solarize Frederick County Initiative

Residential Solar Panels ,Solar Service ,Home Solar PanelsFREDERICK, MD: Today SES was informed by the Frederick County’s Solarize Committee that they were chosen to be the official Solar Water Heater installer for the Solarize Frederick County initiative.

The pilot program aims to increase installations of solar water heaters, as well as solar electric (PV), systems in Frederick County County.  The financial incentives include County grants and volume purchase agreements, in addition to pre-existing state and federal grants.  Astrum Solar were selected as the solar electric (PV) installer.

While funds last, all Frederick County residents are eligible to apply for the incentives that reduce the cost of a solar water heater (or solar electric PV system) by up to 85%.

Residential Solar Panels ,Solar Service, Home Solar Panels
Written by Anonymous

DC Condos Use Solar Energy to Pre-Heat Hot Water

Residential Solar Panels ,Solar Service ,Home Solar PanelsWASHINGTON, DC:  Solar Energy Services, Inc., in partnership with third party solar developer Skyline Innovations, recently finished the installation of a solar water heating system for Shoreham North, a condominium building in downtown Washington, DC.

The solar thermal system includes 26 collectors southerly mounted on the roof, closed-loop plumbed to a 1,500 gallon solar storage tank inside the building.  The system is expected to reduce the building’s water heating utility bill by about 30%.

Commercial Solar Energy Residential Solar Panels
Written by Roger Perry

Would that be One Tank or Two, madam?

Solar veteran Roger Perry discusses the pros and cons of One Tank Vs Two for Solar Back-up

Commercial Solar Energy ,Residential Solar PanelsAll solar water heaters in Maryland, D.C. and the mid-atlantic provide a family of four with around 75% of their annual hot water load. Most customers use their existing electric or gas sources for the remaining 25% backup (usually needed dead winter). When installing a solar system one question that will come up is “Should I use my existing tank and have it fed by the solar system?” or “Should I remove my existing tank and use the electric back-up that comes in the solar tank?”. A couple of situations make this an easy decision;

  1. An existing electric water heater with no room for another tank. This is especially satisfying and cost effective if the existing tank is leaking or on it’s last legs. It’s like getting $1500 off the cost of a solar system because that money would have needed to be spent anyway. In this case you would definitely chose a single tank system.
  2. The other is if you have a gas water heater. While not as cut and dry as the example above, using the electric element would mean using a higher cost fuel for back-up (not so much with propane). Much of this extra cost would be mitigated because the single tank back-up would not run as much because it would be affected by solar input without running a faucet. You would need to run an electric circuit (30 amp, double pole breaker). This may be difficult or very easy depending on the breaker box location and available space in it. Most jurisdictions will also require a master electrician and a permit for this to be done. In this case, I think, most people would shy away from a single tank system unless there was just no room for another tank.

Let’s look at the pros and cons of each system;

SINGLE TANK PROS

  • Smaller footprint
  • Less heat loss
  • Electric element can sense the solar output and not come on from stand-by losses
  • Can go “all solar” just by turning off the element (essentially flipping a switch).

SINGLE TANK CONS

  • Less back-up in cloudy weather (can be compensated with a larger solar tank which will have a larger back-up capacity).
  • Less solar storage when the element is on (can be compensated for with a larger solar tank which will have more solar storage).

TWO TANK PROS

  • Usually greater back-up capacity

TWO TANK CONS

  • Greater heat loss
  • Larger footprint

The secondary backup tank can’t sense the primary solar tank temperature unless a faucet is turned on, sending the water through the two-tank system.  This causes the second tank to turn on from stand-by losses when the primary solar tank is already plenty hot.

Going all solar requires operating valves as well as turning off back-up.

Personally I’m a fan of single tank systems. For the most part their two main drawbacks can be compensated for by installing a larger tank. An upgrade from a 80 to a 120 gallon solar tank is only a few hundred dollars. For a 50% increase in solar storage it is a small price to pay.