Vertical-axis wind turbines have been around for thousands of years, yet we still haven’t seen modern turbine producers make a dent in the wind market. Why is that so? Listen to Renewable Energy World’s Podcast

Most wind experts say that VAWTs are simply inferior to traditional three-bladed horizontal-axis turbines. That’s why the technologies only make up one percent of the small wind market. The industry has also been historically dominated by sketchy companies and “inventors” who pushed fraudulent or under-performing technologies to unsuspecting consumers. With today’s renewed interest in renewables, consumers have forgotten about many of the past problems and are again fascinated by such machines. Just go to youtube and type in “vertical axis wind turbine” to see the dozens – if not hundreds – of technologies that folks are touting as the revolution in wind. “There’s nothing new here,” says Small-Wind Expert Ian Woofenden. “We see people coming up with the same old ideas” for harvesting wind on rooftops and within neighborhoods. Woofenden is one of a number of wind experts who loath vertical axis technologies for both residential and utility applications. He sees them as a threat to consumer and investor confidence in wind.

However, along with what small-wind veteran Mike Bergey calls the “Bozos and Scheisters,” there are also a handful of companies in the space that are being a bit more cautious and transparent in their approach. For example, Nevada-based Windspire Energy recently opened itself up to testing by the National Renewable Energy Laboratory. Another company, New York-based Urban Green Energy, had its power curve third party verified by China’s largest wind certification body. (The company manufactures products in China). Historically, VAWT companies commonly presented theoretical power curves as “proof” of how great their technology is. The American Wind Energy Association also set up a small wind certification council this year that will help consumers make better choices. Many of the leading VAWT companies support the move, saying that it will help filter out much of the noise in the market. “We believe in testing. As time goes, certification will be more prevalent and we’ll be right there with everyone else,” says WindSpire CEO Walt Borland. With that said, many of the “leading” VAWT companies are tiny compared to other small wind companies. The performance of these products will determine whether or not companies move beyond experimentation and curiosity. Even the most anti-VAWT folks agree: A more rigorous testing and certification process will be good for everyone involved.

Well, good for everyone except the Bozos and Scheisters. To hear from Ian Woofenden, WindSpire and Urban Green Energy, check out this week’s podcast, linked above.

Originally posted by 1Bog: http://bit.ly/cHYV0C

In general, DIY projects are a good thing, from hacking IKEA furniture to making bento boxes. But solar panel installation is something that’s best left to professionals, both for your own safety and to protect your home.

1. You could hurt yourself.

Whenever you’re working with electrical wiring, there’s a very real risk of electric shock. As soon as you attach wiring to a solar panel on your roof, it’s immediately live. If you don’t truly know what you’re doing, you could be seriously injured. When you wire your inverters, you could come in direct contact with electrical energy; worst-case scenario, this could cause electrocution. Even a minor shock can cause an involuntary muscle reaction as you jerk away from the the electricity, and if you’re on your roof, this could cause you to fall. Which brings us to our second point: it’s also dangerous to work on steep roofs, high above the ground, especially if you’re not experienced.

2. You could damage your house.

Although it’s rare, you could put holes in your roof when you install solar panels, which is another reason why it’s important to choose someone with the right skills– and avoid going the DIY route. If installed incorrectly, there’s also a small risk that the solar panels could later cause a fire. Experienced installers, like those we select after careful vetting at 1BOG, can give you peace of mind.

3. You might not install the panels optimally for best performance.

Unless you’ve done a lot of research, you won’t know how to find the best location for your solar panels in order to get the most power from them. Professional installers know how to assess your home and determine where to put the solar panels based on direction and shading, with a consideration of how the position of the sun will change throughout the year.

4. You might be breaking the law.

If you’re not a certified electrician, you can’t legally connect the wiring for your installation. There are very good reasons that a professional is required, as listed above. Even if someone has an electrical contractor license, that doesn’t mean they have the right skills to safely and correctly install solar panels, so it’s really necessary to work with someone who’s well-qualified and experienced in the specifics of solar power.

5. Figuring out how to install solar panels takes a long time.

Aside from the time it takes to figure out where to locate the panels and how to install them, you’d also need to research the number of panels you need for your electricity consumption, the type of panels to choose, the correct inverter to choose, and more details about the equipment itself. Actually performing the installation of solar panels also takes time, and usually happens with a full crew of installers. Using professional installers ensures that you’re getting the best equipment for your home, installed safely and properly (with a multi-year warranty from the installer to boot). Sign up for One Block Off the Grid to let us do the research for you and choose a company with high-quality panels, high-quality installation practices, and stability as an organization. And keep yourself safe and sound, and off the roof.

Photo Credit. Post via 1bog.org

 Here is the EPBB rebate explained by the CSI website:

Owners of solar systems less than 50 kilowatt (kW*) may apply for an up-front cash rebate known as the Expected Performance Based Buydown (EPBB)**. Program Administrators calculate a customer’s rebate using the expected performance of the owner’s system based on equipment ratings and installation factors such as geographic location, tilt, orientation and shading. Customers receive their incentive payment in a lump sum after their system in fully installed and interconnected.

And here is the PBI:

Customers with solar systems between 50 kW* and 1 MW must* apply for the Performance Based Incentive (PBI) structure. PBI incentives are a five-year stream of fixed monthly payments determined by the actual output of the system, as metered and reported to the utility. After January 1, 2010, all systems greater than 30 kW must choose the Performance Based Incentive structure. The PBI incentive path is available at any time to ANY size system. The table below shows the effect of prices as these step declines occur, with current prices in the three territories highlighted in yellow. Residential and commercial incentives are the same price in each step; however, local governments and other tax-exempt organizations receive a slightly higher incentive because cannot qualify for Federal Investment Tax Credits on their solar systems. The table below shows the rebate levels available at various steps, and information on currently applicable step in your region is available at the California Solar Initiative Trigger Tracker.

However, there is a catch. In order to use this great incentive, the homeowner or business must “record the output of the PV generator”, and “pay for 5 years of data communication and performance monitoring and reporting services” (emphasis mine). So who are these Performance Monitoring and Reporting Services? After some major digging through the beaurocratic labyrinth of CSI and Pacific Gas and Electric’s websites, I found this list:

1. Applied Power Technologies, Inc.
2. Deck Monitoring, LLC
3. Draker Laboratories, Inc.
4. Energy Recommerce, Inc.
5. Enflex
6. Enphase Energy
7. Fat Spaniel Technologies
8. Locus Energy
9. NergyOS, Inc.
10. Recurrent Energy
11. SatCon Power Systems
12. SolarCity
13. Thompson Technologies, Inc.
14. Trimark Associates, Inc.

So there you are! The list of the 14 privileged Performance Monitoring and Reporting Service providers. These chosen few capitalize on every solar installation in the state of California.

Solar PV panels are rated in Watts-peak. This means for example, a solar panel rated as “200W” really means that (±3-5%) this is the maximum or peak instantaneous wattage that can be produced under STC (standard test conditions). STC assumes several important factors that are not always present at a specific customer location. STC is stated to be a condition where the panel temperature is 25°C (77°F) and where the panel is perpendicular to the sun, and where the sunlight conditions produce 1000W/m² of insolation (direct sunlight). A 200W panel will not produce 200Wh (watt-hours) each hour all day long, rather, it will produce up to 200Wh per each hour of full strength insolation. In many parts of the US, the adjusted hours of insolation will be between 5-6 hours per day in the summer, and 3-4 hours per day in the winter. The table at right provides a snapshot of insolation values for a few major US cities. Efficiency The efficiency of a PV panel is often misunderstood and misused in the sales process. A “high efficiency” panel is usually not the best value for the customer. Efficiency of a typical poly- or multicrystalline silicon PV panel may be in the range of 14%-16%. Efficiency of a more expensive monocrystalline panel will usually be in the range of 15%-18%. Some very expensive panels are reaching the 22% range. At a practical level, efficiency only affects (in a relatively small way) the amount of roof-space that a panel will need. For example, 200W panel at 14% efficiency will take up about the same amount of roof space as a 210W panel at 15% efficiency, but at a lower cost/W. In most cases, the customer’s cost/W is the more important factor; the best cost/W will be found in the lower efficiency ranges. Power production When a PV system does not produce the expected amount of power, the cause is often traceable to the original system specifications and design that were proposed during the sales process. Most power production problems seem to occur not as a result of faulty installation, but rather as a result of faulty expectations or faulty design. These kinds of problems are mostly created during the specifications and design phase leading up to the sales proposal, and are most often the result of cost-cutting mixed with an effort to indulge the customer’s aesthetic considerations, without full disclosure of the ramifications. The customer doesn’t want the panels on the front of the house (which is the south-facing, best location), for example, or says “it looks better over there” — right where a telephone pole casts a small shadow that travels across the row of panels every afternoon as the sun moves (of course the pole can’t be removed). Partial shading of a panel or string of panels can dramatically reduce the performance of the array. Within each panel, if a single cell is shaded, its lowered performance will cause a bottleneck effect that lowers the output of all other cells to match it. Within a string of panels, a shaded or partly shaded panel has the same bottleneck effect on all other panels. Mismatched orientation causes the same effect. If some of the panels in a string face in different directions or have differing tilt angles, all of other panels in the string will drop production in real time to match the lowest performing panel of the moment. There must be a separate string used for each angle and tilt used. It is important to show the customer much more than the rated output peak of the system. It’s far better to do a conservative calculation of average output considering all of the factors including temperature, sun angles, transient shading, inverter inefficiencies, etc. A proper calculation will ultimately be confirmed by measured production just a surely as an overstated capability will be noticed and challenged. There are many other sales and preliminary design issues that must be considered, like string sizing, inverter selection, logging and monitoring capability, cosmetics and aesthetics, tax credit and rebate issues (and surprises). We hope to address many of these topics in future articles.

John Williams is COO of Solar Panels Plus, 533 Byron Street, Suite E, Chesapeake, VA 23320 USA; ph.: 1-757-549-1494, e-mail: jwilliams@solarpanelsplus.com .via Solar PV installations: Beyond “measure twice, cut once” – Photovoltaics World.

1. Equipment grounding
2. Grounding Electrode
3. Grounding Electrode Conductor
4. Bonding
5. Grounded Conductor

Equipment Grounding has to do with the green wire that is, under normal operation, not supposed to carry any current. It’s job is to connect all non current carrying metal parts in the system back to the grounding electrode. A Grounding Electrode is a metal thing that IS connected to the earth. The list of possible grounding electrodes and how they are and can be used to ground your system is pretty extensive. Article 250.52 in the code book deals with this. They can be things like concrete encased rebar, metal water piping, building steel, or ground rods brutally pounded 8’ into the earth (these seem to be the favorite). A Grounding Electrode Conductor is the wire that connects the Grounding Electrode(s) to a main bonding point. Bonding is tying the Grounding Electrode to the Grounded Conductor (we’re not there yet) and the Equipment Ground. The Grounding Conductor is the white wire. It does carry current to complete electrical circuits back to ground. The grounded conductor is only supposed to be bonded to ground at one point in your system (white wires and green wires don’t get hooked together except at the main service. Except when there are exceptions). These terms are used interchangeably only by people who don’t speak NEC speak. Article 690.43 of the NEC is about Equipment Grounding for solar installations. It talks about the green wire that goes along with the PV circuit conductors and bonds all non current carrying metal parts – module frames, rails, racks, j-boxes, combiner boxes and etc. The 2008 code also allows for the use of listed devices that facilitate the bonding of the metal parts together such as the WEEB connectors: http://www.we-llc.com/WEEB.html. There’s lots about sizing of conductors in this section that swing you back and forth from 690 to 250. I’m not going to go into that here. Article 690.47 is where it really starts to get fun. GROUNDING ELECTRODE SYSTEM. I’m going to focus on section (C) that applies to systems with both AC and DC grounding requirements. Here’s the basics:

1. The DC grounding system shall be bonded to the AC grounding system.
2. Size per the largest requirement.
3. A single conductor shall be permitted to be used to perform the multiple functions of dc grounding, ac grounding, and bonding between ac and dc systems.
4. Sized based on sum of inverters
5. A common ground bus shall be permitted to be used for both systems.
6. A common grounding electrode shall be permitted to be used for both systems, in which case the grounding electrode conductor shall be connected to the ac ground system bonding point (the ground bus in the main service panel).
7. Grounding Electrode Conductor sized per largest requirement.
8. For systems with utility-interactive inverters, the premises grounding system serves as the ac grounding system (back to # 6 & the ground bus in the main service panel).

Section (D) of 690.47 is where several installers and inspectors seem to get tripped up. It’s new to the code in 2008 and serves an important purpose but should not be thrown about to rashly. The idea behind installing a grounding electrode is to give the electrical system a reference to ground. If the wiring from a particular system gets too far away from that reference the potential between the real ground and the grounding conductor can be too great. So the code makes us install ground rods at outbuildings and tie the equipment grounding conductor to the grounding electrode conductor. This mainly has to do with the ability of a short to trip the circuit breaker but I won’t go into that. The same concept of installing additional Electrodes (ground rods) is applied here to a solar array.  If the solar array is more than 6’ away by ground from the premises wiring electrode (690.47 (D) Exception No. 2) then additional electrodes are required. The verbiage about “as close as practicable to the location of roof mounted photovoltaic arrays” is what gets some inspectors excited about seeing another ground wire run down the lee side of the house with sweating electricians pounding more and more ground rods all around the premises. Let’s go back up to 690.47(C)6 & 8. Unless we are talking about a roof that is over a building that is 6’ away from the building with the main service, or a pole mounted system that is that far away, then we don’t have to talk about additional ground rods. Safe and simple is my motto for a good solar installation. If it takes additional ground wires and electrodes to make a system safe then we must do it. But if we make our systems more complex and ugly while achieving no greater compliance with the code or safety then we are loosing on several levels. My rant has run its course. More to follow.

- Jonathan Lewis

According to an article by Earth2Tech, Fat Spaniel is rolling out two new product lines this year:

The San Jose, Calif.-based solar software company [Fat Spaniel Technologies], plans to announce on Tuesday that it has developed a set of software called Lifecycle Management solutions that also interpret data from its customers’ projects, anticipating and solving problems to help make the most of those solar assets. The company says that some of its software can reduce total maintenance costs by up to 30 percent. The first two of these products, Solar Plant Vision and Solar Operations Services, are geared toward operating and maintaining solar projects. Aside from helping keep solar plants at their most productive and cost-effective, maintenance is crucial to make sure that these projects retain their value as assets, said Tom Tansy, vice president of marketing at the company. This is especially important considering that most solar projects change ownership after about 5-7 years because of the way they are financed, and keeping track of those assets, including their service and performance histories, is important. Solar Plant Vision, which is software as a service, is aimed at helping solar-project operators increase the performance of the projects they manage. The technology monitors plant devices, tracks system performance, helps simplify billing and reporting, and provides a portfolio status dashboard that can be used for marketing and energy-consumer education. Meanwhile, Solar Operations Services targets project developers, and Fat Spaniel claims the services deliver increased energy production, system uptime and lower, more predictable costs. The company plans to pass information about the condition of the plants — and recommendations for the most cost-effective steps to keep them running well — to its customers’ maintenance crews or partner with outsourced maintenance companies, Tansy said. Fat Spaniel is selling its new services on an annual subscription basis, with the prices varying depending on the amount of energy-production capacity and the number of plants included in the contract. The company already has upgraded its Insight Manager customers, numbering about 500, to Solar Plant Vision, and the new services will be available to new customers starting in October.

Article Source: Earth2Tech