A great time to go solar!
Good news for our solar customers The price of solar panels has come down a lot this year, with some panels coming down 40 to 50% in cost. There are many reasons including the competition from new Chinese panels on the market. Many of these panels are high quality, but it is important to choose a company that is going to be around to honor the 25-year warranty if needed.
Talking about Solar Photovoltaic (PV) Panels...
Until recently silicon was typically made in 5" ingots. The ingot would be sliced with a diamond saw and 72 5" cells would fit in a metal frame, producting a photovoltaic panel called 24 volt nominal. Now silicon is usually produced in 6"cells and 60 cells now fit in a regular sized frame; these 60 celled PV panels are called 18 volts nominal. Most panels are currently made with 6" cells.
A 12 volt panel, for example, doesn't put out 12 volts but it produces enough voltage to charge a 12 volt battery. It produces around 18 volts and has an open circuit voltage, without a load, of 21 volts.
An 18 volt panel puts out around 24 volts and its open circuit voltage is around 36.
A 24 volt panel works at around 32 volts and its open circuit voltage is around 45 volts.
So you can see that the voltage of a panel can be confusing. With an 18 volt panel, you can put more of the panels in series without getting too high a voltage for a charge controller or an inverter, and at the same time you get more amps -- and it is the amps that do the work.
Silicon modules can be made in either a mono or polycrystaline configuration. A silicon solar panel that is mono crystalline uses a more pure form of silicon and this can produce the most power. Unfortunately, It is more difficult to manufacture a mono crystalline panel and hence they often are more expensive. Poly crystalline panels are easier to make and the advances in technology with poly crystalline makes them approach the efficiencies that used to be only achievable in mono crystalline panels. Mono crystalline photovoltaic panels also have the ability to perform better in high heat areas although some poly crystalline panels can also perform well in high heat. In the spec sheet for a panel is a temperature coefficient. This tells you how much electricity you will lose for a temperature rise in degrees. Panels are normally rated at 25 degrees C.
When an ingot of silicon is cut, the middle slices produce less power than the end slices, which is a major problem for solar panel manufacturers. The low output cells used to be mixed up with the high output ones, but these low output cells bring down the voltage of the whole the string of cells to the lowest producing cells. Recent manufacturing techniques separate low output cells from those with a higher output and a good company can make the same panel with different wattage outputs. The tolerance for a panel with segregated cells would be usually 0 +3. This means that you may find a panel in your order that is three percent higher than the rated output but the panels wouldn't go below the rated output. This is why the zero tolerance is so important.
Another group of panels are called thin film modules. These were created when silicon supplies were scarce but now thin film solar panels have a hard time competing against the new technologies that allow pure silicon to be made out of an inferior grade mined silicon.
Typically a thin-film PV panel can be CIS or CdTe. The CIS panels are Copper Indium Selenide and the CdTe are the Cadmium Telluride panels. CIS panels only have a 15 year warranty and they don't have as good efficiency as a regular silicon solar panel. In addition, Cadminum Telluride panels have to be recycled as hazardous waste and for that reason we have never been fond of them. They also suffer from a reduced efficiency and a reduced life expectancy.
The PTC rating of a panels is called the Pacific Test Condition. It takes into account that the panel would be producing less in the morning and evening while the maxium output would be at miday when the sun is most perpendicular to the panel. The PTC rating is a more accurate determination of how much power a solar panel would produce. The STC or standard test conditions is the output of a panel when the sun is most pependicular to the panel. This is the rating that is used when companies tell you how may watts their panels put out.
There are many solar manufacturers that buy cells from large companies and then these companies put the cells in a frame, put glass on the front with some sort of waterproof backing and you have another company manufacturing a solar panel. The trick is to find a manufacturer that is going to be around in 25 years. The issue is not to doubt the panels' performance in 25 years -- solar panels have been around for decades and the old panels often test out to their original specs and most PV solar companies warranty their panels' power output to be 80% in 25 years. The issue is more one of being able to purchase replacement panels in case of breakage, or to expand an existing solar system. However, you may need a crystal ball to see which companies will still be around in 25 years.
Thinking of Buying a Solar System
Using a Solar Lease?
You may want to read this before
Questions are arising as to how the financing of solar leases actually works. Yes, it's tempting to buy a solar system (sometimes with no money down), but who is actually benefiting the most from these innovative financing schemes?
A recent article in Renewable Energy World shows the beneficiaries of cheap solar PV panels and the ubiquitous solar leases to be not the consumer, but the financing companies and the installers.
The federal tax credit gives consumers a credit of up to 30% of the cost of the installed solar system. If the system is funded using a solar lease, the credit goes to the leasing company, not the homeowner.
However, it appears that the actual cost of the solar system can be a rather subjective number; the solar lease companies may be greatly inflating the actual cost of the system and the losers are the homeowners, the taxpayers and the reputation of the solar industry.
The cost of solar power, particularly with the Federal tax credit, is finally becoming comparable to the cost of utility company generated electricity as the cost of the PV panels continues to drop. However, in the case of solar leases, the cost saving is not necessarily being passed to the customer. One can only wonder how much more the leasing companies will be profiting if a feed-in tariff is ever enacted – as it well should be.
For more information on how well the middlemen are making out as the gap between low cost solar and high utility prices continues to grow, the following article from Renewable Energy World is an eyeopener.
Another reason for the drop in module prices is the availability of raw silicon. REC has invented a process where they can take an inferior grade silicon and with silane gas turn it into a very high quality grade silicon which they sell to many solar manufacturers.
The cost of solar panels has now come to a parity with coal and with nuclear power. However, you cannot build a nuclear plant for less than $6,000 per kilowatt and then you still have to deal with nuclear waste and plant decommissioning. Coal has other health issues which can make it one of the the most expensive ways to produce electricity; it can even be even more expensive than nuclear.
The good news for consumers is that you can currently put together a solar system for way less than $6,000 per kilowatt.
Founded in 2005, ReneSola is a leading global manufacturer of high-efficiency solar PV modules and wafers. Leveraging its proprietary technologies, economies of scale and technical expertise, ReneSola uses in-house virgin polysilicon and a vertically integrated business model to provide customers with high-quality, cost-competitive products. ReneSola solar modules have scored top PVUSA Test Conditions (PTC) ratings with high annual kilowatt-hour output, according to the California Energy Commission (CEC). ReneSola solar PV modules can be found in projects ranging in size from a few kilowatts to multi-megawatts in markets around the world.
We are selling the ReneSola in pallet quantities; additional charges apply for smaller quantity orders.
The ReneSola JC250M-24/Bb and the ReneSola JC255M-24/Bb are packed 25 per pallet. The ReneSola JC300M-24/Ab and the JC310M-24/Ab come 20 per pallet.
Call us for details.
Solar Panels more affordable with state rebates and net metering
Some states allow you to feed your home-produced power from solar panels back into the utility grid and turn your electric meter backwards. Use this net metering or utility-intertie system with a battery backup to provide power when the electrical grid is down.
Many states, including California, offer rebates on the cost of a photovoltaic solar panel or wind generator system to homeowners connected to the power grid. Businesses may be able to take a 30% tax credit for installing renewable energy equipment. (Check with your tax advisor.) Also the Federal Government is working on implementing getting a check instead of taking a tax credit if you might not need a tax credit.
REC has added an impressive series of panels to its product line, the new Peak Energy series. The PE modules, which replaced the AE series, are manufactured using a proprietary process on the raw silicon and the tolerances on the new panels are a low -0/+5%.
The REC PE series modules are produced in a new plant in Singapore using the latest robotics technology. Contact us for pricing on larger quantity orders.
For more information, go to www.recgroup.com
From OutBack Power, the Radian GS8048 inverter/charger
Grid-Interactive and Stand-alone capability in the same package
- 8000 Watts of continuous power
- Unsurpassed surge capacity
- 120/240V split-phase voltage
- Dual AC inputs
- Field upgradeable firmware
- Field serviceable modular design
- Simplified parallel design allows easy installation of systems from 8 to 80kW
- GS Load Center option allows for quick and easy installation
Call for low pricing on inverters.
Off Grid Customers
If you are located in a remote area, we can also provide solar and wind energy products for use in off-grid situations. Let us help you design your system.
2013 Renewable Energy Design Guide and Catalog
The catalog contains sections on solar power, mounting structures, wind power, micro hydro, charge controllers, inverters, metering, batteries, water pumping, and miscellaneous electrical supplies. Also contains useful reference sections on wiring, solar insolation. (250 pages.)
Call us at (415) 388-0838 to order.
Price: $9.50 (includes shipping to US and Canada).
Not all the alternative energy products Beyond Oil Solar sells are on our website. Email us at email@example.com for a competitive quote on other alternative energy products not listed.