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WHERE KNOWLEDGE EQUALS POWER INDEPENDENCE
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Below you will find in order the following subjects listed in bold font. The covered subjects should answer most of your general questions. If after you read these subjects and you have more questions then call us on the phone to be more specific or better yet make an appointment to stop by our Design and Training Center. To Grid (tied) or not to Grid (off-grid), that is the question?
2008 Green Buildings Open House, Saturday 4th October 2008, 1000 to 1600 Mark your calendars now because it is time once again for the 6th annual Green Buildings Open House, which is part of the American Solar Energy Association’s (ASES) National Solar Tour on Saturday 04 October 2008 from 1000 to 1600 hours. Once again Solar & Wind FX will be the Rochester and Finger Lakes area coordinator for the tour. The purpose of this open house is to move people from simply being interested in green building technology into becoming purchasers of these technologies and services. The Open House also offers homeowners and others the opportunity to help spread the word that sustainable design principles and clean energy systems work and green homes are comfortable homes. Stay tuned to this web link for a list of area homes. To Grid (tied) or not to Grid (off-grid), that is the question? Here we are trying to determine whether or not to be attached to the Utility power grid or to produce 100% of all your electrical needs, which is called being Off-grid. There is no right or wrong answer to this question. If you are currently connected to the Utility, you will know this because you get the pleasure of sending them a check every month. Off-grid means that you are taking control of your energy needs and are going to become your own little utility/independent power producer. No more monthly check writing for you. Grid tied continued. Next, let’s check your utility bill to see if there is a fee called ‘Service Benefits Charge’ (SBC) or Renewable Portfolio Standard (RPS). If so you should be eligible to take advantage of an incentive program that is controlled by the New York State Energy Research and Development Authority (NYSERDA). Visit their web site for up to date info, but basically for a residential home the rebate is $4.00 per watt installed. What this equates to is on a 4,000 watt installed system you are looking at a $16,000 incentive. For a wind generator the incentive is currently at 50% of the overall installed cost of a residential system. To give you an, idea this size PV system would provide about half of the electrical energy needs for a family of four in an average size home. I wish to point out that the majority of grid tied system do not have any batteries and if you remember any one thing then remember this, when the utility grid goes down, so do you. In other words your electricity goes out, despite the fact that you have 4kw of PV or wind on your site. This is to protect the utility lineman from being shocked by your system feeding electricity back into the grid. There are ways to provide your family with electricity and keep the utility workers safe at the same time. That's where Solar & Wind FX comes in. While on the subject of the Utilities find below our description of Net Metering . A word of caution on Grid tied systems. As Renewable Energy (RE) is getting more publicity these days and our utility bills cost seem to increase frequently and many states are making funds available to consumers for RE systems. What almost always seem to follow are unscrupulous individuals who are out looking to make the quick buck. I call these people the 'Sharks' of our industry. My peers and I will do are best to educate you and give you a quality system at a competitive price. On the other hand, the Sharks are looking to make the quick sale and move on to the next. An example of this is the Shark may sell an RE system but fail to tell the consumer that when the utility power goes out, your $15k to $30k investment will be worthless with out battery back up. Ask the Shark if they are using RE themselves and could you see their set up. How many systems have they installed? Off-grid is just that. You are off the utilities grid and are now in control of managing you own electricity production as well as usage. Key word here is usage. I’m sure we all remember back to when we were kids and your dad was constantly telling you to turn the lights off in your room. You are no longer polluting the earth by using fossil fuels, nor are you concerned where we will put the nuclear waste from spent fuel rods. You have chosen to leave an inheritance to future generations that you can not place a price tag on. Now there’s a Visa commercial for you. Priceless!! Not to mention how proud your dad would be. After all he is due some credit. Obviously there are many reasons to have a Renewable Energy (RE) system installed for you. However, we normally make this decision based on our back pockets. So just how far from the utility power is your building site? To give you a couple of examples where our Design Center is located our driveway is a half a mile and back in the early 90’s it would have cost us about $22-25k to have electricity brought up to our site. Well that was a no brainer for me. Another site was about the same distance and the client was quoted over $40k. They ended up with a $55k system for a 5,000 sqft home. Their thought was why write a one time check for $40k and still pay a monthly bill till the end of time. So what if your utility quotes you only $10k and you need a $40k system? This is a decision you must make on your own. I can tell you that you will have cleaner power (simple put your electrical appliances will last longer) and more reliable power than the utility will ever be able to provide. No more coming home to having all your digital clocks flashing. Does anyone remember the Ice Storm of 91’ or the Northeast power outage of 02’? Did you know that the utilities have still not made the necessary upgrades to the grid systems infrastructure to prevent it from happening again? Do you remember buck a gallon gasoline? How long before electricity prices catch up to the rest of the world? Our American appetites for electricity continue to grow with an outdated power supply and distribution system. The major difference in an off-grid home is we use a set of batteries to store your electricity in for non sun/wind times. See, in a grid tied system the utility grid is your battery. Basically an infinite battery, that is until the utility goes down. In off-grid systems we use wet lead acid batteries, similar to which you have in your car or truck. However, the batteries are much larger and are designed around putting out energy over the long haul verses your car/truck which is designed to output a lot of energy over a few seconds for starting purposes. Still unsure as what to do, either Grid-tied or Off-Grid. I personally would like to see everyone become Off-Grid electrical users and never have to worry about electrical reliability or what next months bill will bring (surprise!) and the awareness of electrical usage that being Off-Grid brings to you each and everyday. On the other hand if you are already attached to the grid then I would suggest having us design a system that would allow for the possible future expansion and movement towards going Off-Grid. To put it simply, take the States incentive/tax credits monies and then after five years you have the option to go completely Off-Gird. Why? See in order to get the NYSERDA incentive one of the requirements is to provide electrical production data for five years. After that you can choose to do whatever you would like. What I mean by that is your obligations to NYSERDA is complete. Now if we design a system with the intentions of going Off-Grid in the future, you can then pull the plug on the utility and become your own private utility. Let it be known that if the design is as such, then the overall system cost will be a fraction higher. You now have the knowledge and we hope you will use it to move towards power independence. So please read on. In New York State there is a Net Metering law. Not all States have this. Net Metering in its simplest form means that the utility purchases your excess electricity at the same rate they sell it to you for. In order for this to happen a utility grid interconnection agreement must be signed with your utility company. Not to worry for this is something we do for you. How this works is on a month that your PV or Wind generator system makes more energy than you can use, then your utility will credit you for that month and forward this credit into the following month. If you continue to have a credit each month for twelve months consecutively then your utility will pay you for this excess. However, they are only required to pay you what is referred to as the avoided cost. In laymen’s terms, this is known as the wholesale cost. This normally equates to about three to six cents per kilowatt, depending upon your utility company. Site survey, this is where a PV/Wind professional like myself travels to your site to evaluate your PV and wind potential. Below is a brief explanation of what you can expect as a result of a Site Survey. Ø The visit to your location will take anywhere from 1 to 3 hours. Ø We will determine the location of the PV array and or wind generator, as well as the placement of the Balance of System (BOS) components. Ø Use a device called a Solar Pathfinder. This is to determine any shading that may occur during the daylight hours for a 365 day period. Ø Take digital pictures before and after shading (generally trees) have been removed. Also need pictures of Service Entrance equipment and PV mounting location(s). Ø Discuss your electrical AC and DC power needs. Measure size and record name plate data off large electrical devices. Ø Record Service Entrance Panel manufacture and model/serial number. Ø Need to determine wire run distances for calculating voltage drops. This can severely effect the cost of the system because of copper pricing and it is used in our system design. Ø Review your utility bills for the past twelve months. Please allow us to take the originals back to the office or provide a copy. They will be returned once the survey calculations are completed. Ø Tour of your home to determine any high energy use appliances and ghost/phantom loads. A ghost or phantom load is an electrical device that even though it is off, it is still consuming electricity. This is the educational part of our job. Ø Discuss the use of a Kill-A-Watt meter to be used to measure specific electrical devices. This helps you truly understand just how much electricity it takes to run your appliances. Ø Armed with the above information we then return to the office and do the calculations to determine the correct equipment best suited to meet the needs of your project. Ø Provide you with a budgetary quote and a basic description of the prescribed system that will meet your project needs. The budgetary quote will reflect any incentives or tax credits. Of course any tax credits should be verified with your tax accountant. We can not emphasize enough as to how important it is to have a Site Survey done. The cost for an average Site Survey is approximately $450 to $800 depending on expenses and travel distances. Of course the high cost of diesel fuel is not helping us out here. Besides the travel time to and from your site, plus the time spent on site with you, we will spend about 8 to 12 additional man hours putting all the information together. If you feel apprehensive about paying this for the service then you probably are not ready to commit to spending $20k to $80k for an RE System. Half of the fee is due at the time the survey visit is done. The other half is due once we have completed the budgetary quote. 100% of the site survey fees will be applied towards the installation of your system. It has been our experience that 8 out of 10 clients that walk through the doors of our Design Center wanting to install a wind generator end up going with PV. I must remind you that each client’s site is different and the use of either wind or PV is unique to your site alone. Each of these devices is out in the harsh environment 24/7, 365 days a year. A PV array is basically a non- moving device that absorbs the suns’ light. Where as a wind generator is placed atop a 100 to 130 foot tower and is subject to wind gusts, rain, ice, snow and lightning. The big difference is now you have a mechanical, rotating device with blades that flex and wear. You also have bearings and lubricants that must operate in all temperatures. A wind generator needs to be visually inspected at the very minimum of every six months and the tower should be climbed or lowered annually. For the annual inspection all bolts and guy wires need to be checked for tightness. At some point the generator will need to be removed from the tower and if you do not have a tilt up tower this will require the assistance of a crane. The maintenance of a PV array is to keep the snow removed and change the tilt angles every season. People always say to me that we don’t get enough sun to just install PV. We love hearing this. After the first year of having the Design Center up and running we experienced a problem with our large wind generator in November. We would be unable to repair the generator till the summer months. This meant that we had to run our business entirely off of PV. We did this successfully with only two separate days of runtime on our back-up fuel (yuk) powered generator. All of our off-grid systems are designed with back-up propane fueled generators. Now don’t get me wrong I enjoy watching a wind generator and don’t mind the maintenance. When I set out to start this endeavor my goal was always to provide my business and home with 100% of renewable energy (RE). By design our hybrid system comprised of both PV and wind has achieved this. However, for a client that does not want to be bothered with the periodic maintenance of a wind generator then PV is the way to go. Please do not misunderstand our message here. Our job is to educate you the consumer on selecting the correct product that best meets your needs. The final decision to go with either wind or PV is ultimately yours to make. PV panels need to be placed in an area that has no shading between the hours of 0900 and 1600 hours. That’s four o’clock in the afternoon for non military personnel. PV panels can be mounted on a roof, on top of a ground mounted pole or ground mounted via a series of aluminum rails. This will depend of course on your site. It seems that most people want to place these on the roof of a home. It is our company’s policy not to do this. This is not to say that we won’t but we must first educate the client on why it is better not to. Ø When mounting to a pitched composite roof this will require many penetrations via lag screws. This presents the potential for a leak. Ø Since we know that the roof is extremely hot during the sunniest periods, this increases the temperature of the PV array. As the roof temperature rises the arrays' electrical output decreases. Ø Can not adjust for seasonal tilt angles of the PV array, thus unable to get the full payback from you PV system. Ø Not safe to climb the roof in the winter months to remove snow from the PV array, thus unable to maximize your electrical output. Ø Not only difficult but also unsafe to service the array in the winter months or severe weather. Ø Most PV panels are warranted for 20 years. What about your roof? Also, how many roofs (reroofs) are currently on your structure. You will have to replace your roof before the PV array. Even for someone that is about to have a new roof installed, the array will outlast your new roof. Ø Under the panels is a good place for critter nests and tree debris to collect. We know of a case that a squirrel made a nest under the panel and chewed its way through the roof into the clients home! A word to the wise, there are installers that will place systems which allow for some partial shading. Here’s our thought on that. You, the client just spent thousands of dollars on PV panels. As an installer/designer I want to squeeze every electron out of those panels to give you the best bang for your buck. Any wind generator needs to be about 30 to 50 ft above the tallest obstacle with in a 500ft diameter of the tower base. Under no circumstance is a wind generator to be mounted to or on top of a structure. There are three main tower types. A Self Supporting (SSV), guyed wire lattice and tilt up tower. The SSV is generally you most expensive, however if you don’t wish to cut or trim vegetation around the guy wires or look at them this is the way to go. Both the SSV and guyed wire tower will require a crane for the installation and anytime that the generator will need to be removed. A tilt up tower on the other hand requires a winching system or tractor to raise and lower. Also the tilt up tower is not climbable. Ideally, all wind sites should be on flat ground. This is even more important for a tilt up tower. There are several types of batteries on the market today which are used to provide energy storage. But only three of them are cost effective and commonly used in our RE industry. The three types are absorbed glass mat (AGM), gelled electrolyte (Gel Cells) and flooded. These are all lead acid based. The AGM and gelled batteries are sealed and are virtually maintenance free. These are usually used in outdoor applications and grid tie systems where they are normally only used for short periods of time. Although the batteries are sealed, they still do emit gasses. Thus a sealed battery box needs to be provided along with either a passive or active venting system. In general, these batteries are more costly then their flooded counter parts. Flooded lead acid batteries, also know as deep cycle batteries, are what we normally use in our Off-grid projects or where the client has large energy requirements. Along with flooded lead acid batteries comes required maintenance. As the batteries charge the water/acid mixture inside turns to a gaseous state. The gases are then vented out of the battery box to the outside atmosphere. Water level of each cell needs to be maintained so these levels will require monthly inspection. This can vary depending on usage. Other maintenance that is required approximately every six months is equalization. Here we give the batteries an exact over charge for a period of time which is based on battery size and current state of charge. The equalization is best done with a fuel powered generator. The purpose of the equalization process is to bring each battery cell up to the same voltage and specific gravity. It also mixes up the water and acid mixture as well as cleaning the lead plates. There are items that we can add to the battery systems to help minimize the maintenance. It should be noted that batteries need to be kept in a very clean and 77 degree F environment. So you’d like to know how long before the battery bank will need replacement? There are many variables that come into play. One of the battery manufacturers that I commonly use comes with a prorated warranty of 10 years and a life expectancy of 15 years. I have several banks of these batteries in different environments but none of them have been in service long enough. However, all maintenance and measurements seem to back up the manufactures claims. Only time will tell. This is by far the most frequently asked question that I receive. “How much will it cost to install a PV or wind system”? There is no standard answer to this question either. The best I can give you are some ball park numbers which are based on my experience. Before I get to the numbers you must understand that a site survey needs to be performed and there are many questions that need to be answered before a solid number can be given. For a description of what a site survey entails click on Site Survey. Remember that a number given to you will probably not work for you neighbor or friend. Each system is very site specific. For an average family of four in a 2,400 sqft home, a grid tied system will run around $20k to $55k after any incentive programs or tax credits. Approximately $30k to $80k for an off-grid system that consists of either a PV or wind system. This does not include the price of a back up generator. Also there are no NYSERDA incentives available for off-grid systems. I am hoping this will change in the future. But don’t hold your breath.
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