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Q:i live in a 1 bed 760 sq apartment and my power goes out some times due it is old building and i don't want to be with out power so i'm asking what kit would i need to put on my deck to power my tv computer or laptop and my small stero either one not all at once for about 6 hours or lest i work 16 hours a day just something to relax before bed or 1 before work

A:

When it comes to emergency power, it is critical to know the power consumption of the equipment you intend to run. For example, the power needed to run a Refrigerator is substantially less than powering a 10w light bulb. If a emergency power system is built for a 10w light bulb it will not provide enough backup power for a refrigerator. Most appliances will have ratings on the manual or on the power adaptor showing the power consumption of the equipment. Record the values and multiple by the number of hours you intend to run the equipment to get the daily power consumption. Do this calculation for all the equipment you wish to run off.

Back up or off-grid systems consist of the following core components: solar panel, deep cycle solar batteries, inverter, charge controller, racking and miscellaneous components. SolarTown has a great learning and research section with articles that will provide an overview of system requirements and how to build a solar energy system. If you have any questions while you are putting together the backup system feel free to contact SolarTown directly or by using our new Live Chat service for any question or support you may require. After you've done your calculations, if you decide that a larger system will not work for you, you may want to take a look at some of the Brunton power packs. These power packs can be found under portable solar modules in our store and can provide enough power to power small devices and are often used for emergency backup power for small items.

01-29-2012 by kenny Category: Solar Electronics

Q:I want to install a 2 wire submersible deep well pump and use solar to power it. The pump is 1hp, 230 volt, 8.28 amps. How many panels and batteries would be required to run this around 4 hours per day?

A:

Many submersible pumps can run off solar panels, and you have a wide selection in SolarTown's solar module section. Your system and equipment looks like it is built to run off 230v which means the power source that works optimal with the submersible water pump falls in the conventional source category. To size up a system to power a 230V device may not be feasible considering many solar modules are built between 12v - 24v and batteries are built up to 12v.

If you have not yet purchased the equipment, a suitable alternative to explore may be a solar water pump system that can handle the water extraction rate required for your application. There are several Solar Water Pumps, for example SunRotor Pumps, built for submersible applications. SolarTown published a learning article or how to guide on sizing and selecting a Solar Water Pump.

Another approach, if you already possess the equipment, is to offset the energy consumption of the pump system by feeding back solar power directly back to the grid. This arrangement will provide you with energy credits generated by the solar energy system which then indirectly offsets the power consumed by the water pump. There are many ways to get the job done, it really comes to what you want to achieve and how you want the system to be built. Feel free to contact us directly for more information.

01-16-2012 by Jeff Category: Solar Water Pumps

Q:What size inverter will I need for 1.65w of panels please?

A:

To properly size up an inverter it comes down to choosing between whether you want to have a central inverter or micro inverter. If the system is off-grid then you will have to consider other options. On grid-tied systems and heading toward the route of central inverter make sure your inverter can handle to the output of your home solar powered system. In your situation you're probably looking at a central inverter that can handle 1.65kW of power coming from your solar panels. Sunny Boy make some of the best central inverters in the market, a SMA2000 will work with well if you head toward a central inverter system. Fronius and Outback also make top notch central inverters so take a look at some of their inverters.

If you want to head toward a micro inverter system, take a look at Enphase Microinverters. Micro inverters may be an option depending upon what you want to achieve. For homeowners choosing between the two can be a challenge, SolarTown has learning and research articles comparing a central inverter to a microinverter system to make choosing the right system easier for homeowners.

There may be a few other variables to consider but one thing I always remind homeowners and many forget to remind homeowners is "Will the homeowner want to upgrade the system in the future? If that is indeed the case, maybe a larger inverter will make more sense so that you will not need to buy an additional central inverter.

If you have any questions, feel free to contact SolarTown or use our new Live Chat.

12-16-2011 by Ned Category: Solar Panels

Q:I have a SUNROTOR SRPS4-150-24-SS solar water pump connected to 3 135 W panel in series. This makes 405 W using SRC-P100T controller. I do not have the performance curve of this pump, but I do not think I could get 2.8 GPM with 131 FT of head having this pump configuration. To me, it has the panel power but not the pump power.

A:

If you currently have three 135w solar modules, you can configure them in series which should generate about 6 GPM at the given lift of 131 ft. How you configure the solar panels whether it be in series or parallel can result in greater or lower flow rates at different lifts. Once you determine your environmental variables, you can easily adjust the SunRotor Solar Water Pump to meet your water extraction goals.

11-05-2011 by ROD M Category: Solar Water Pumps

Q:I am wanting to know how many amp hour batteries I need and the size of solar panel I need to charge them to run 233 watts of power about 6 to 8 hours a night

A:

In order to properly size up the battery system, we need to know more about the component or at least the technical specifications for what it is that you will be running, the location of the system and if there is a shading issue. Once we have that information we will be better able to assist you. In general, deep cycle solar batteries should never be discharged more than 20% - 40% because the deeper you discharge the solar battery the shorter the life of the battery. As you discharge more of the battery, the life of the battery diminishes. Real life circumstances can be difficult to replicate but if you follow that above rule you will maximize the life of your battery. Due to circumstances you may discharge the battery all the way, just keep in mind that full discharge will dramatically reduce the life of the deep cycle battery so MINIMIZE complete discharge as much as you can. The number of solar panels required for your application will vary with conditions and battery sizing. At minimum you're looking at three solar panels rated at 235w or above. The easy part in properly configuring the system is that you will need to know the technical specs of the equipment and the environmental conditions which you should already have.

10-16-2011 by Clyde Category: Solar Electronics

Q:I want an estimation on how much it would cost to purchase enough solar power to operate one 25 cu.ft. chest freezer. I live in south Georgia. Panels, inverter, etc

A:

A SunDanzer DCF225 solar freezer, our largest DC solar freezer, will operate with either a single 175w solar module or a combination of up to 750 watts of solar modules depending upon environmental conditions. In your case, it would be difficult to size the appropriate system without knowing more about the technical specification of your solar freezer. Solar freezers will require more power than a conventional refrigerator so if you are looking to safely store food or other products, without freezing, maybe a refrigerator will be more suitable. If however you are looking to freeze food or other products then you're better off with a freezer. Please visit our section on solar freezers and solar refrigerators suitable for your application. If you have the technical specifications for your solar freezer, please contact us and send us the information so that we can provide assistance in sizing the backup solar power.

10-10-2011 by grady b Category: Solar Outdoors

Q:I am looking to get started in the solar panels and I was wondering how many watts worth of solar panels do I need to run 2 laptops one power adapter says that it its out put power is 19.5v - 3.9 amps and the other laptop out put power is 19.5 v and 3.34amps what size of panels and how many batteries do I need and what size of inverter do I need to run this system about 3 to 5 hours a night maybe little longer

A:

Since laptops do not use too much power, it shouldn't be difficult to provide backup power to a single unit. Usually the setup will require a solar module, solar inverter for time daytime charging. If you're planning to have backup power at night then you will be looking for a solar module, charge controller, battery and inverter. As for specific wattage, take a look at the technical specification of the laptop power adaptor. If you provide the adaptor specs and the computer/battery type, we can get a better idea of what equipment will be needed. You can optimize the system further by determining how fast you want the laptop to charge under the sun and whether or not you have any limitations such as only a solar portable module solution (something you move around with). Let us know and we can try to find the right solar solution to your inquiry.

10-06-2011 by clyde k Category: Solar Electronics

Q:I have a 230 watt solar panel. I need to run a refrigerator. What inexpensive one can I use? Can I run an energy star one? The lowest wattage ones use about 1.05 kWh per day. How many panels would I need? I live on O'ahu.

A:

 A conventional AC refrigerator can be powered with solar panels but in order to do so you need to know what the technical specifications are so that you can properly size the solar energy system. It really comes down to what you are planning to run.If you know the manufacturer and the model number, you can access the information by contacting the manufacturer and send that to us and we'll work with you to find a solution.

As for solar refrigerators, SolarTown offer many solar refrigerators for your specific storage needs. Visit our solar refrigerator section and you will find different sizes suitable for your application. Some will require a separate battery and charge controller component while others are direct drive solar systems.  Feel free to contact us if you have any further questions.

10-04-2011 by Rick Category: Solar Electronics

Q:I need to light a pathway that is in the shade. Do you have lights that have the separate solar panel placed in the sunlight.

A:

The solar path lights we have here at SolarTown will come with an extension cable from the solar module to the first solar light. It really boils down to the solar pathway light and how the manufacturer designed the solar light. Take a look at our solar path lights section for a wide selection of lights that matches your pathway design theme which is where you will also find information regarding the lead wiring. If for some reason the information is not published, feel free to contact us directly for further assistance.

09-28-2011 by Barbara H Category: Solar Lights and Garden

Q:If I'm consuming around 300Kwh daily, what would be the size of my panel(s) to install? What is the ratio for energy generation (KWH)of panels per square feet or square meter with 50 efficiency?

A:

If you are consuming 300kWh per day, you must either have a huge home or have a small factory somewhere. By way of comparison, in the US, the average home is consuming roughly 1000 kWh per month. How much space you will need to install solar panels on your home to meet this entire consumption (we really hope that you are not using that much in your home) depends on a number of factors, such as location, efficiency of the panels, and the size of the panels. The efficiency of solar panels today is in the 14-17% range. Take a look at our learning article on choosing solar panels. If the roof on your home is a constraining factor, you will definitely want to compare the size of the solar panels you are considering. As we point out in that article, if you only had 500 square feet, the number of panels could vary from 24 to 32 panels.  The efficiency of panels has improved since we wrote that article, but talking in round numbers, if you are using 110,000 kWh per year (based on your numbers), you are going to need roughly 5,500 square feet of space on your roof or mansion or factory, whatever you have, to accommodate roughly 330 solar modules. Call us up at SolarTown and we would be happy to take your order.

08-23-2011 by Amir A Category: Solar Panels