It’s been a while since last post but here we will have a ton of solar PV design information and photos. First and foremost, this will be a generic solar system design that assumes installation of Solar PV panels on an average home in New England. This guide is aimed for the home owner (or business owner) looking to have a solar systems installed on a roof of their house (office building/store/etc).
Just to let you know, it is highly recommended that you get a professional solar integrator to do it for you. There is just too many things you need to consider when designing a solar array installation, and unless you are experienced in the field of electricity and roofing, leave it to the pros. This guide will help you understand what goes on from step one (contacting a solar integrator) to final step - having a complete Solar PV array on your roof (or on the ground) and supplying you with “free” electricity. For a detailed overview of solar system costs and pay-off period, refer to Solar PV system design guide
Solar PV System - Basic design.
This is an essential step that determines the feasibility of having a solar system installed. For example, the solar system has to be positioned so that it faces south, and have as little shading as possible. If neither of these is true in your case, than solar system is not for you.
So, the site survey will be the first step, and a solar integrator you choose to work with will perform it. Site survey takes about 3 hours on site, and you can add driving time to it. Therefore it is safe to assume that site survey will cost you anywhere from $125-200 depending on a solar company you are working with.
If you are not serious about getting a solar PV system installed, and just want to know how much it’s going to cost you, this guide is for you. Don’t waste the solar integrator’s time with something you can do yourself.
Basic solar PV system info:
Average household in the US consumes 500-750 kWh (kilowatt-hours) of electricity per month. To find ot how much you electricity you use, gather your last 12 electric bills and add up all the kWh you used. Devide this number by 12 and you’ll have you monthly average electricity use. Notice that in the summer you use more electricity than in the winter (unless you have electric heat, which is the MOST expensive source of heat, and we recommend you change it before installing a Solar PV system).
We will assume that your monthly average electricity usage is 500 kWh. We take the lower end of the spectrum as most homeowners begin to use LESS electricity once the solar system is installed. The install energy-efficient appliances and lighting, turn off lights when they don’t use them and so on. Basically all the things they’ve never done before. This also allows them to have a smaller capacity solar array installed as the demand goes down.
How many KW will you need?
So, if you use 500 kWh per month, than your annual electricity usage is about 6000 kWh. As a rule of thumb, 1 kW solar array will produce 1000-1200 kWh of electricity per year, when it is installed in an unshaded area. This number accounts for all the rainy/cloudy days and grid power fluctuations which may know out your inverter for a period of 5 minutes to 2 hours, depending on the quality of your electric lines and local transformer station.
Average residential solar installation is about 2.5-3 kW, and if your goal is to be 100% net-zero (to suplly 100 % of your electricity) you are looking at a system size of 5-6 kW.
Site Survey
Step 1 - Identify southern exposure and possible shading.This is an essential step that determines the feasibility of having a solar system installed. For example, the solar system has to be positioned so that it faces south, and have as little shading as possible. If neither of these is true in your case, than solar system is not for you.
So, the site survey will be the first step, and a solar integrator you choose to work with will perform it. Site survey takes about 3 hours on site, and you can add driving time to it. Therefore it is safe to assume that site survey will cost you anywhere from $125-200 depending on a solar company you are working with.
If you are not serious about getting a solar PV system installed, and just want to know how much it’s going to cost you, this guide is for you. Don’t waste the solar integrator’s time with something you can do yourself.
If you do not know where the south is, use a basic compas to identify if your roof has a southern exposure. On a sunny day look at your roof to see if nearby trees and/or buildings throw off a shade on your roof. Do this in the mornig, noon and around 3 or 4 pm. If there is no shade, you are in good shape. If there is a shade from a tree, you’ll have to cut it. If it is you neighbor’s home, talk to them about removing the top floor of their house, mentioning that a shade will reduce your electricity production. This is a joke of courese. If there is a shade from a nearby buildng, depending on how much of a shade it is and how many hours per day it is present, will determine if a solar electric system is feasible for you.
Why we believe that Metal Roof with Solar is the most practical, and sustainable option for residential Solar PV installations?
In the next two weeks we will have a complete guide to designing a beautiful, long-lasting Metal Roofs with integrated Solar PV technology. Watch this video and read on:
The main problem associated with general Solar PV systems that you can now see on many homes around the country, is the fact that an asphalt shingles roof will fail much sooner than the Solar panels, and when that happens, those home owners will be faced not only with re-roofing expense, but also with complete removal of solar array and re-installation. This MUST be performed by both the roofer and the solar integrator, as the roofer alone will 99% of the time screw things up. And bear in mind that roofing warranty will usually not cover demages to the solar equipment, let alone all the possible short-circuit type situations.
The additional cost associated with these procedures should be at-least the same as the cost of the new roof itself. Think about it: Electricians unlike roofers have to be licensed. Apprentice electrician needs at-least 4 years of schooling/work experience. This is like an undergraduate degree. Master electrician needs another 4 years. Therefore, electricians usually charge $75-100 per man-hour. You’ll need at least two electricians for this job, which will take a whole day to remove the panels and another day to put them back, if not more.
The math is simple: 2 guys * $75/h * 8 hrs. * 2 days = $2400 plus any possible parts and supplies that may be required. So let’s say it costs you $2500 extra. In some parts of the country that is how much an average 1200 sq. ft. cape house roof will cost today with the material.
Metal Roofs vs. Asphalt shingles
Unlike very “popular” asphalt shingles, metal roofs are pretty much permanent. They are for the most part, produced from recycled metals, and when installed by a trained professional, should not leak for decades. Read more about residential and commercial metal roofing .
Metal roofs combined with Renewable Energy technologies can create a perfect combination of light, long-lasting and affordable solution for Solar Electric and Solar Hot Water, as demonstrated in the image to the below:
There are other numerous benefits to having metal roof combined with Solar PV and other renewable energy technologies. When looking at metal roof vs. asphalt shingles, also consider that metal roof will save our land fills from getting more shingles dumped there in 10 years or so. Combined with beautiful looks, you get a permanent roofing solution, various solar technologies, and when paired up with geo-thermal system, you can easily design a 100% energy-free home, with a great curb-appeal.
Check back in a couple of weeks for a complete Solar Metal Roofing Guide.
Finally I got a chance to learn Solar Systems installation and design with lots of hands-on and theory!
This is the first of the series of reports to be posted this fall. Reports will include new technologies and methods of solar installation, as well as other renewable energy topics.
For the first time in 2 years there is a Solar Training program running at the Community College of RI (CCRI). Their previous instructor moved to Maine, and there were no people willing and able to teach the class. There is now over 400 people on the waiting list, so I guess I’m on of the 15 lucky ones.
After reading through 100s of Renewable Energy websites and grasping all the theoretical aspects of Solar Photovoltaic systems, I had to finally get my hands wet. Unfortunately, except for one solar distributor out of MA, offering overpriced 1 and 2 day “Solar Training” programs, I could not find any college or tech school offering any courses in Renewables and Solar.
It all started over a year ago. Back in the summer of 2007 a course brochure from CCRI listed a Solar Training Program being offered in the Spring of ‘08, but no detailed info was provided. Only a contact phone number, of a person running a “Lifelong learning program”, an equivalent of a continued ed. program offered by most colleges for “working professionals”.
After making over 20 calls to CCRI and speaking to more than 30 people, most of whom never heard about this class, I finally got my name on a waiting list, that was aimed at electricians who want to install Solar PV systems. Myself being a roofer, I was not their target audience in the first place.
As spring of ‘08 rolled on, there was still no instructor. By late may, after a few voice mails I finally received a call that the Instructor was finally found and the class was scheduled to run in the fall ‘08. On one rainy June day, when I could not “roof”, I got in my car and drove to CCRI’s Lincoln Campus, only to find out that person in charge of the program was at the Warwick campus, so I had to drive through half the state to talk to them and secure myself a seat in the class.
As i got to Warwick campus, the person I was looking for, left for the day (at 1 pm) so I had to run between 5 differnt offices to find someone else who new anything about the class. After talking to a few people I had them put my name on another list of people who interested in the class. However, nothing was certain at that moment as the registration for fall simester had not yet begun.
Finally in July I got a letter with a Course Brochure and registration form, which I filled out and mailed back the same day. A week later my Credit Card was charged for this course, and now I am on my way to becoming a “Solar Installer and Designer”. Unfortunatelly I cannot actually install any Solar Systems, since I’m not a Licensed electrician. But i can certainly design one and have the electrician do his part.
Things learned in todays class:
Besides the regular Solar System Design diagram that includes Solar Panels, wiring, the Inverter, disconnects, meters, breakers panels, etc., I actually learned that in New England an average angle at which a fixed solar system should be installed is 42 degrees. Optimal for the summer is 25 degrees and for winter it is 55 degrees.
Also, whenever designing a roof-mounted solar array, a structural survey must be done to account for wind and snow loads.
Fortunately for us, we install roof-integrated thin film solar systems, so all these aspects do not really concern us, as there is no additional weight added to the roof, and since PV panels are part of the roofing systems, wind uplift is taken care of during roof installation.
Other valuable lessons:
Whenever a solar system is installed, a “power survay” should be done to reduce any power loads an install energy-efficient appliances and equipment to reduce electrical power consumption. Double benefit right there.
Things to discuss in next posts: Insulation and Energy Efficiency of your home.
I know it’s May 1st, and you are thinking about beach, sun-tan and barbecues, but now is the prefect time to start thinking about the next winter season, which is not that far away, and by the time it come, it is in your best interest to be ready. Especially if your home is not yet fuel efficient.
Why $5 heating oil? Well, look at the diesel price today. Here in Massachusetts (which has some of the lowest fuels prices across the United States, and is second only to NJ, which has no gas-tax and thus has nation’s lowest gas price) the price of diesel in most places is above $4.45 per gallon and given that gas jumped 35 cents in last two weeks it is safe to assume the $4-plus gas and above $5 diesel/heating oil by the fall / winter time.
Thank you Mr. Bush. Oh, and it is such a pity that Exxon-Mobil missed their earning expectation and made only $10.89 BILLION in net profits, instead of $11.65 billion projected by analysts.
Any way, enough sarcasm, we need to make our home use less energy. First thing you can and should do, is replace those old, drafty windows.
Despite the fact that this is Green & Solar site, I’m going to recommend Vinyl windows. That is right, not the wood-green-built but vinyl. Why? It is simple. Remember the Practical Approach thing? The the carbon-footprint of vinyl windows is less than that of wooden windows if you include the heat loss accumulating over time, and the vinyl window are cheaper and more fuel efficient - therefore they are Practical!
Here I’ll discuss a specific type of vinyl windows - Alside UltraMaxx line, that comes with triple glazing, double low-e and two argon packets. Combined together, UltraMaxx gives you 6.67-r value. Bear in mind that standard and well-built double-glaze, low-e argon window has an R-value of less than 4.
Why Alside UltraMaxx? Well, this is not a commercial paid for by Alside. I just love those windows, and had personally installed many of them. They are very-well built, and have the most durable and sturdy frame of all othee Alside lines.
You may ask why not Anderson or Harvey or Pella windows? Well, non of those actually make a tripple glaze windows, so my choice is Alside.
Bloomberg radio in NY area (1130 AM) announced today that oil is trading at $119.40 a barrel. It is all great, except for one thing - the cost of oil production for “Big Oil” companies like Exxon-Mobil, Shell and Chevron did not change much in the last few years. So all of this ridiculous rise in oil price is purely speculative, and
This site is dedicated to the renewable energy, sustainability, EV and Plug-in Hybrid (PIHV) cars, green energy-efficient construction and resource conservation - all from a practical stand point.
Here I’ll discuss a specific type of vinyl windows - Alside UltraMaxx line, that comes with triple glazing, double low-e and two argon packets. Combined together, UltraMaxx gives you 6.67-r value. Bear in mind that standard and well-built double-glaze, low-e argon window has an R-value of less than 4.