Solar Energy Show

Ed Murray Talks About Commercial Solar Hot Water Systems by Barry Cinnamon 366248

Easy Home Energy Audits by Barry Cinnamon 366248

Rooftop solar panels only work when they are in direct sunlight. So if you have a partially shaded roof, the output of your system will be lower than if there were no shading. And if your roof is heavily shaded, then rooftop solar is probably not going to be cost effective. The reduction in output that shading causes depends on the type of shading, the orientation of your roof, and the use of microinverters or optimizers (these module electronics can help reduce shading problems). The most common examples of rooftop shading include trees, chimneys, neighboring structures, and utility poles. A small amount of shading -- perhaps from a vent pipe or utility pole -- will not have much impact on overall system output. But trees or other structures can have a big impact. A good rule of thumb is the object creating shading should be twice as far away as it is higher than the panels. There is a home around the corner from me with a solar system on the west roof, and a big Magnolia tree right next to the house shadi

Fires in homes are generally caused by kitchen mishaps, heating system fires or electrical malfunctions. When it comes to fire safety, the solar industry's track record is excellent -- with only a few documented cases in which the solar system actually caused a fire (generally due to improper wiring or equipment malfunctions). Unfortunately, when home fires do occur, rooftop solar panels can become an impediment to a firefighter's ability to safely and quickly put out the fire. Firefighters must turn off the power to the rooftop system so that the panels are no longer energized; this is not always possible with high-voltage DC systems. In many cases, firefighters vent the roof so that smoke can escape and they can pour water on the source of the fire. With solar panels covering the roof, firefighter's ability to vent the roof over the fire is limited. Improving fire safety as it relates to rooftop solar systems is being approached from two directions. First, new solar panel, racking and inverter standards a

Here’s a nightmare for you: at night, when you’re asleep and you think things are quiet, there are vampires sucking power out of your house and increasing your electric bill. The fact of the matter is that every plugged in electrical device in your home uses a small amount of standby power -- even if you think these devices are off. When I explored each room of my house with a wattmeter, here is what I found: · Computer devices used 66 watts: printer, cable modem, multiple wireless routers, laptop charger, mini-speaker · Communications used 16 watts: iphone charges in several rooms, cordless phone · Entertainment systems used 57 watts: flat screen TV, cable box, sound system, DVD player, subwoofer · Kitchen appliances used 6 watts: microwave, coffee maker, dishwasher · Other culprits used 23 watts: cordless vacuum, clock radio (remember those?), irrigation controls, garage door opener, furnace, thermostat transformer, doorbell transformer These devices added up to 168 watts of 24x

Technologies, companies and business models in the solar industry come and go. But even in the relatively new solar industry, history repeats itself. Disappearing tax credits and incentives, financing scams, unreliable technology, societal doom (Y2k) and gloom (nuclear winter) -- it’s all happened before. We can learn a lot about building a sustainable solar businesses by talking to the solar contractors who have witnessed several of these boom and bust cycles over the past 20+ years. My guest on this week’s Energy Show on Renewable Energy World is Pat Redgate, CEO of Ameco Solar. Pat has been installing solar thermal and solar PV systems at Ameco since 1974. Having successfully ridden the “solar coaster” for 40+ years, he has some terrific advice for solar customers (both residential and commercial) and solar installers who want to get into the business for the long term. Please join me as Pat talks about the first wave of solar in the 70s and 80s, what happened when the tax credits disappeared, how he sel

According to Doc Brown, Marty McFly’s DeLorean needed 1.21 gigawatts to travel back in time. To put this in perspective, new gas power plants are about 0.5 gigawatts, typical large utility scale solar power plants are 0.1 gigawatts, and the average rooftop solar system is 0.000005 gigawatts (5,000 watts). Although it takes a lot of solar panels to generate the power our society needs, solar is now one of the cheapest and cleanest sources. And “clean and cheap” is now the world’s preferred power source: in 2013 the world added 143 gigawatts of new renewable energy generating capacity compared to 141 in new plants that burn coal, natural gas, or oil. Fossil fueled power plants have not just taken a temporary back seat to renewables - we are witnessing a long term transition in the world’s energy sources. The price of wind and solar power is on par or less than fossil fuel electricity. Renewable energy prices are on a steady pace to get cheaper, while gas and oil will inevitably go up as supplies are constrain

I’ve spent a lot of time over the past 15 years talking to homeowners about rooftop solar. More kitchen table chats and walks around the house than I can count. Some of the basic questions I hear again and again. Because they are new to solar, some of the most important questions do not even occur to homeowners. On this week’s Energy Show we’re going to address some of the more obscure questions that homeowners should ask... and installers should be prepared to answer: Why do I need a building permit for solar? What happens if I run my electric meter backwards and don’t tell my utility? Can I use the power from my solar system during a blackout? Who covers the warranty on my solar installation and solar equipment? Is 3% or 4% or 5% a reasonable projection for electric rate escalation? If I sell my house, how will the new buyer value my solar installation? Will that tree to the south of my roof shade the system and reduce its output? Do I need to clean my solar panels? Is there a catch with a “no money down”

We’re talking about religion this week. Did I get your attention? How about if we talk about climate change, more renewable energy, dirty fossil fuels and solar subsidies? OK, we’ve already covered these topics. But now the Pope has chimed in with his “On Care For Our Common Home” Encyclical. I’m probably the worst person to comment (I got kicked out of Hebrew School). But I did read all 180+ pages of his Encyclical. There is no doubt in my mind that the Pope’s analysis and commentary will definitely affect U.S. politics related to clean energy. First, the Pope describes the problem succinctly: pollution and climate change. Some quotes: “Very solid scientific consensus indicates that we are presently witnessing a disturbing warming of the climatic system." “Problem is aggravated by a model of development based on the intensive use of fossil fuels." “Urgent need to develop policies so that, in the next few years, the emission of carbon dioxide and other highly polluting gases can be drastically reduced, for e

Things have been changing pretty quickly in the light bulb business. In the course of a few short years, Edison’s filament bulbs have become illegal, marginally more efficient halogen bulbs have become the default choice in hardware stores, twisty compact fluorescents (CFL) have pretty much had their day in the sun, and specialty LED bulbs are now inexpensive and available in virtually every shape, size and color. When I researched residential lighting a few years ago my conclusion was to go with CFLs because they had the lowest operating costs - but you had to tolerate their slow start up and poor colors. Since then LED bulbs have plummeted in price. Moreover, one can buy LEDs that fit virtually every fixture and claim to work in dimmers. So now it’s almost a no-brainer to go with LEDs. Nevertheless, there are still challenges with LED bulbs. Although they all indicate a 22.6 year lifespan, I have had a number of them burn out already. Not all are as dimmable as they claim. Some of the bulbs are too bulky

Water from Desalinization by Barry Cinnamon 366248

The sun is shining brightly on your rooftop solar panels (or the panels you hope to have). But how can you tell if those photons falling from the sky are actually turning into useful electricity? Since there are no moving parts to a rooftop solar system, it can indeed be difficult to tell if you are getting what you paid for. Fortunately, there are four easy ways to keep an eye on your system’s performance. Check the green light on your inverter, check to see that your meter is running backwards, check your electric bill, and check your monitoring system. 1. If you have an ordinary string inverter (that big box hanging on the wall near your electric meter), all you need to do is make sure the green light is on and that the inverter’s display indicates that power (measured in watts) is being generated. Usually you should see peak output around noon, and on a sunny day this output will usually be about 75% of the rated DC output of your system. 2. Another way to check your system’s operation is to see if your

People with rooftop solar systems almost always ask about using batteries to store their energy for nighttime use. Tesla recently announced an off-grid battery storage system, SolarCity announced a home backup power system, and a dozen other companies already have comparable products on the market. These announcements have re-energized (grin) the hype and excitement in this new product category. But are these systems practical and will they save you money? For the vast majority of homeowners, the answer is “no” to both questions. Only if you have a completely off-grid application -- such as a cabin in the woods -- can the new generation of lithium ion battery backup systems combined with solar be more practical and cost effective than traditional lead acid batteries. If you are currently on the grid, energy arbitrage makes no sense at all: with current electric rates it is simply not cost effective to generate your own energy with solar during the day and use it at night (or buy cheap electricity at night an

Unlike other home appliances, HVAC systems and vehicles, there is virtually no maintenance required for a well-installed rooftop solar system. So unless you are paranoid, or just cursed by bad luck, there is no need to pay anything extra for a service contract or scheduled maintenance. Why are rooftop solar systems so reliable? First, because the solar panels themselves have zero moving parts, use tempered glass and anodized aluminum (better than most windows and skylights), and are covered by a 25 year manufacturer’s warranty. Second, because top quality microinverters carry a 25 year warranty and string inverters carry a 10 year warranty — and based on industry experience, the real-world performance of quality inverters has exceeded their warranty term. And third, because flashed rooftop mounting systems using all aluminum and stainless steel components will last at least as long as a homeowner’s roof. If your last name is Murphy you may ask: “what could go wrong?” If you live in a dusty or dry area, you

Understanding A Home Solar Sales Pitch by Barry Cinnamon 366248

A rooftop solar system is an expensive up-front investment. The typical 5 kw system costs about $20,000 – or $14,000 after the 30% investment tax credit (which expires on 12/31/16). Solar leases and loans have made it possible for hundreds of thousands of homeowners to go solar without any initial up-front investment. Now there is a new solar financing product called PACE that makes it easy for just about any homeowner to qualify for a low interest solar loan. PACE stands for Property Assessed Clean Energy. A PACE loan is repaid as part of a homeowner’s annual property tax assessments, and is automatically transferred to the new owner as part of the property. For example, a $20,000 rooftop system could be repaid in 15 annual tax bill payments of about $1,500. If the home were sold after ten years, the new owner would simply take over the remaining five years of principal and interest payments. Interest rates and terms on PACE loans are about the same as standard bank loans. Since the loan is secured, intere

Running A Successful Solar Business With Pamela Cargill by Barry Cinnamon 366248

Paperwork Makes Solar More Expensive by Barry Cinnamon 366248

How Do Solar Companies Find Their Customers? by Barry Cinnamon 366248

We've made great progress with renewable energy -- but from an almost zero base we still have a long way to go. Fortunately, the path is clear. California is already over 12% with a combination of hydroelectric, wind and solar (unfortunately not much hydro this year). Getting to 50% only requires the deployment of existing technology. But can we get to 100%? It depends on whom you ask. Our society has made these transitions before, with new energy technologies disrupting the incumbents. 200 years ago 95% of our energy came from wood; by 1900 it was 50% coal; and by 2000 it was a mix of coal, nuclear, oil and gas. The Union of Concerned Scientists have published a plan for renewable energy to provide 80% of our electricity by 2050. Why stop there? Solar enthusiasts like me want to go for 100%. This goal is possible: there is a recent Stanford paper entitled “100% Wind, Water, Sunlight (WWS) All Sector Energy Plan for the 50 U.S. States.” This plan is surprisingly realistic when one considers the rapid rate o