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Q:Does solar roofing work in area that experience heavy snowfall in the winter? Any information you can provide to us regarding the solar roofing would be greatly appreciated.

A:

Home solar panels and snow. Home solar panels can be installed on the roof even in areas that experience snow. There are currently more solar installations in Colorado than states that are warmer so snow conditions will not preclude you from putting up a solar energy system on your roof. In any environment, if snow, leaves or debris cover the solar modules, you will not get much energy out of your modules, so the trick is to make sure that your solar energy system is free snow so that the modules can gather in the maximum amount of solar rays.

Solar modules installed in snowy environments should be installed at an angle not only to maximize energy output but also to act as a snow removal tool. When snow accumulates on the surface gravity will force the snow to fall off which will increase the energy yield in the morning. If snow does accumulate on the panels (like the nor'easter that hit the NE), the sun shining in the morning will also play a role in melting the excess snow. If however there is a lot of snow, some prefer using snow removal agents but you can also lightly sweep away the snow as long as it is not frozen.

Please keep in mind safety when performing any aggressive snow removal. Mother nature will usually do the trick otherwise.

01-04-2011 by Scott A Category: Solar Panels

Q:i need to solar power my antique motorhome.it is about 16 by 10 by 10.i want a dc powered heater, 5' tall frig freezer,12" lcd tv, laptop, and pc all powered.how many batteries, what kind of batteries, how many solar panels and what kind? and what kind of inverter?etc.

A:

A solar energy system can be a very good answer to your RV needs, but first you need to find out how much power you actually use. Find out the power consumption required by a DC heater. An Energy Star fridge uses about 110 watts when running (older fridges can consume up to 500 watts when running). A laptop consumes about 150 watts, and a 12" LCD TV might consume another 100 watts when running. All of these power usages are then multiplied by the hours/day used, for a total power - or load - profile. Determine the power requirements of each device and multiply by the hours/day it runs. Then you can easily calculate how many panels you will need. By way of reference, in most parts of the country a 2500 sq. ft. home can be powered with a 4 - 6kW arrays, or 18 230-watt solar panels. The needs for a solar energy system for your antique motorhome will be much less and if you're smart about the appliances you choose you can reduce the number of home solar panels you'll need.

12-28-2010 by hahn Category: RV and Marine

Q:I want to put a solar submerisible pump in... However, i have three wells, all have working 230 volt 1 hp pumps, what is the least expensive way to convert to solar and retain those pumps. I envision a asolar array (24 vdc? or higher?) charging solar batteries, then to an inverter, I would like to use a 110 volt inverter and astep up transformer or should i simply change the pump to 110volt. the 230 volt inverterss are terribly expensive. I use the wells for watering cattle, and have pressure tanks,,, What type of system would work for me ???? Help!

A:

We are hearing from a lot of farmers and ranchers who want to use solar water pumps. We have a good selection of solar water pumps that may fit your needs, but you need to be careful about your design for your solar water pump system. We understand that you are trying to pump about 1200 gallons per day. One product that may fit your needs is the SR-4 SunRotor Helical Rotor Solar Pump. The SR-4 comes with a maximum lift of 250 ft for optimal configuration which will easily meet target depth of 120 ft. At 100 feet, the SR-4 can pump out 6.9 GPM or 9,936 gallons per day. As you increase the lift, the daily water output will be reduced. Most configurations will vary, but for your environment the SR-4 is more than enough to get the job done. The SR-4 can achieve the water output you are targeting. The SR-4 will require a single solar panel rate at 185w or above with additional mounting hardware and wiring. We suggest that you purchase a solar water pump package that will include everything you will need to set up your solar pump. Feel free to contact SolarTown directly if you need further assistance with your application.

12-10-2010 by Pat O Category: Solar Water Pumps

Q:I have a tile roof and wanted to find out whether I should give up on going solar, or are there some ways that I have solar panels installed on my tile roof? Can you tell me what my options are?

A:

Tile roofs often have great exposure to the sun, as they are commonly located in the desert southwest. 300 days of sunshine can payoff! The trick is finding the right solar mount for installing your solar panels. Often times it is the array's mounting feet that prove to be the most challenging aspect of an installation. My own house is asphalt-shingle, so the big challenges were 1) verifying the roof was structurally sound enough to support the weight (and wind load) of the array and 2) finding the rafters!

If you have a tile roof the chances are that the underlying structure is modern and strong enough to support the weight and wind load of the array. The key is selecting the right solar mount and securing it to the rafters. Typically roof rafters are spaced 16 inches apart, allowing feet to be secured every 48 inches A 10-panel array with two rows of 5 home solar panels in portrait orientation will take up about 200" horizontally and 130" vertically.If you mount array standoffs every 48 inches and use 3 rails for the array you're looking at 5 standoffs across and 3 standoffs vertically. 5 x 3 is 15 standoffs. More important you need solar roof mounting specific to the tile on your roof. You can use a Unirac Creotecc Roof Tile Hook, which are secured to the rafter beneath the tile, then carry rails on the side, front, or on top of the tile. Tile hooks can be used with any standard racking system. Good luck with your solar energy system.

11-08-2010 by RileyR Category: Solar Panels

Q:I have a house in south lake tahoe. I get tons of sun on a nicely pitched roof all year long. Do you have solar panels that deal with night time snow?

A:

Home solar panels may be installed even in areas that receive lots of snow.  There are currently more solar installations in Colorado than many states with warmer climates. Solar panel installation in areas receiving lots of snow should be installed on an angle. When snow does accumulate on the surface, gravity will force the snow to fall off (natural process).  If there is snow accumulation on the solar modules, the sun shining in the morning will melt off any excess snow.  A secondary option is a tracking mount for the modules which can be adjusted to prevent the snow from accumulating on the panels. 

08-24-2010 by david b Category: Solar Panels

Q:hi, i live in cape town and i would like to buy a solar panels for household use:lights,radio,tv and if possible iron and i don't know where to buy it or which one to buy.can i buy a +-15 watt or +-12 watt and with which invector can i use it with?

A:

We get this question a lot from people who are looking for a home solar panel system. They want to know how large their system needs to be, but that depends on how much energy you use, and you will need to do an energy audit to figure that out. And then you need to know how much sun you get where you live.

First, you need to determine how much energy you are consuming, Identify the appliances your using (light bulbs, radio, TV, etc) and find out the wattage consumed by each item. There should be a label on each appliance indicating its power consumption. For example, a typical 19-inch color TV consumes about 60 watts when running. Identify the wattage values of every appliance you want to power and apply the following formula:

Item x Quantity x Watts x Hrs/Day Used x Days/wk used ÷ 7 days = Watt Hours Consumed

Next, find out the number of peak sun hours (or daily insolation) your city receives. Cape Town is on the southern tip of Africa and it looks like it receives between 5 - 6.9hrs of peak sun. This is a considerable range so check some local resources.

Once you know the load you consume and the amount of peak sun you receive, you can calculate the size array needed. If you're just powering a TV, the size array needed would be estimated as follows:

TV x 1 x 60 watts x 4 hrs/day x 7 days/week ÷ 7 days = 240 watt-hrs /day, or .24kWh/day

If you receive 6 hrs of peak sun at your location, you would need (roughly) the following size array to power the TV:

.24kWh/day ÷ 6 hrs per day ÷ .88 PV Temp losses ÷ .84 derate factor ÷ .9 inverter efficiency = .06kW array

.06kW array x 1000watts/kilowatt = 60 PV array watts.

In this scenario a 60-watt panel would provide enough energy to offset the energy consumed by a 19-inch color TV. This answer assumes the solar energy system is grid-tied. Please do not assume that an appliance that there is a one-to-one match on watts consumed with watts on an array! That's just how this example worked out.

Find out how much energy you want to make and your local solar irradiation and we can specify a system to match this consumption.

08-10-2010 by france Category: Solar Panels

Q:Can TSM-220PA05 be used in a 12 volt system? I notice the voltage output is about 30 V. I hav a MPPT Charge Controller 15A, Wellsee WS-MPPT15 12V/24.

A:

The short answer is a qualified yes, because it depends on the solar charge controller. As long as it is a "step down" charge controller, it should be able to dial down the voltage to voltage level suitable for the batteries.Be sure to read the spec sheet on your charge controller! You may want to take a look at Outback FX models as well as the SolarBoost 50 that we offer. These charge controllers both have this capability.

07-28-2010 by Paul S Category: Solar Panels

Q:what harware do I need between a panel array and my house panel to do a net metering system. I am concerned that I don't have power to my panels from the grid and also that power company personnel are protected in the event of a general outage.

A:

If your current solar energy system is off grid, and needs to be changed to grid tie and connect with your local utility then it will require an inspection. It will also need to be connected to the grid through a grid tie inverter that feeds current into your breaker box via a circuit breaker or into the electric meter directly. All of the grid tie inverters SolarTown sells will shut-down in the event of a power outage. It sounds like you have an array that is DC only - the solar inverter is the item that changes the DC to AC and shuts down current in the event of a power outage. You will need to enter into a net metering agreement with your utility in order to send electricity onto the grid with your solar array. Contact your utility to find out what type of meter you currently have. Some meters will only run faster (and charge you more) if you hook an array up to them - so be sure you contact your utility and find out their requirements for net metering!

07-21-2010 by dave w Category: Solar Panels

Q:We are building a small cabin on a remote island and are thinking of using solar panels vice propane gas for stove and refrigerator. Neither has been purchased but would like good ball park estimate of 1) solar panel needs just for standard size family fridge and 2) solar power needs for both fridge and small 4 burner stove with oven.

A:

Commonly a refridgerator is one of the largest energy loads in the home. Be sure to choose an efficient one! If you are completely off grid then it likely makes sense to have the fridge use the same power source as the stove. Stoves and refridgerators have distinctly different tasks, and a propane stove makes more sense than an electric one. Electric stoves require a lot of electricity to run through their resistive burners. A propane stove may make the most sense.

Propane refridgerators are available but I have never used one. Electric fridges are getting more and more efficient, so when you shop for a fridge, make sure it has a very high R-value (insulation), a small current draw when operating, and separate freezer and fridge storage. Do not buy a side-by-side model. Make sure it is energy star rated, and the compressor is located on the top (this is why many freezers are on top - the freezer temperature naturally moves downward).

Propane is still carbon-based and won't turn on your lights for you. If the cabin is only being used a few times a year then you could easily power the rest of the cabin (and an electric fridge) with a 1 - 2kW solar energy system. The trick is installing solar modules in a good solar window with a reliable charge controller and deep cycle solar batteries with adequate amp-hour capacity. You don't want to show up at the cabin with solar batteries overcharged or out of power. If you're gone for months at a time you likely want to unplug the fridge when you leave.

It is important to select the most efficient products you can find so you know what they draw on a yearly basis. Once you know the loads the cabin will use (in watt-hours/day), we can specify a system to meet this need. Calculating electric loads is a matter of identifying the load (fridge, lights, radio) and how many watts they use on a daily basis. This can be gleaned from the yearly power estimate provided by the manufacturer and dividing this by 365 days per year. Contact us when you've identified the what appliances and other accessories you plan to use at the cabin. Enjoy the design process!

07-20-2010 by david Category: Solar Panels

Q:2400 sq ft house. What would be the total cost for a solar system for Air & Heating. Dallas TX. area. What systems should I consider.?

A: 

Every home is different and the size of your solar energy system will differ depending on what your needs are. We assume that you mean that you would like to purchase a solar energy system that would cover all of your electricity needs. You should first do an energy audit of your home and see how much electricity you are using and you will find that you should be able to take some relatively inexpensive measures. Through these energy audits you should be able to save as much as 30% of your electricity usage.  Then you should determine what your needs are. We are just assuming that your average monthly usage will be about 900 kWh per month. In Dallas, Texas, your solar radiance is approximately 5.3 kWh/sq. m/day. Your system size to cover 100% of your needs would be roughly 7 kW and you would need about 700 square feet on your foot to install this solar energy system. We offer discount solar panels in packages that could meet your needs. Please take a look at some of the solar package solutions we offer.

07-18-2010 by Doug P Category: Solar Panels