The Basics
Is solar a clean power source?
Solar is a zero emission energy source; including both pollutants (CO2, SO2 and NOx) and noise. This makes it the most environmentally sound energy source.
Is solar a cost effective option for me?
Solar offers long term savings on energy bills and is cost efficient when analyzed on a cost per kilowatt hour (kWh) delivered basis (when rebates and incentives are included).
Is solar able to protect me from rising electricity rates?
A solar photovoltaic system will enable the homeowner to effectively fix a substantial portion of electricity costs over the expected life of the solar system (+30 years).
Is there asset appreciation associated with a solar PV system?
A solar system will increase the value of a home as it reduces the ongoing annual running costs of the property. Installing a solar electric system also enables the homeowner to capture federal, state and local solar rebates and tax incentives.
How long will a solar system last? How much maintenance is necessary?
Solar panels typically last more than 30 years and have manufacturers guarantees of 25+ years. Solar power systems have few, if any moving parts and once installed, require very little ongoing maintenance; they typically need washing to remove dust every few months.
What size solar PV system do I need?
The size of the system depends on individual household energy usage, and whether you want to completely replace the local utility with a solar PV system.
There are esssentially 3 options when sizing a solar PV system.
1. Optimized system size: An “optimized” solar system will cover only the most expensive tiers of power purchased from your utility. Most lower cost tiers of power will remain for you to pay. (With solar you’ll only have one electric bill annually after installation). The lowest tier of power stays historically low, in California it is legislatively protected for low income people. All customers have an average of 340 kilowatts of electricity a month of low cost, Tier 1, electricity available for use. The “Optimized” system size theoretically has the quickest “payback time”: time that it takes for the monies that were going to pay utility bills to pay off the cost of the solar PV system.
2. GoSimpleSolar “Optimized Plus”: This system covers all but the lowest cost Tier (as described above). This system will have a slightly longer payback, but greater long term returns. Due to economy of scale and lower installation costs per solar panel, the installation of a medium size system which covers high and middle cost power may payback in a time period equal to or just slightly higher than the “Optimized” system, yet the long term returns much greater. If site conditions make for an simple installation, and it fits in the customer’s budget, this size system proves the most popular.
3. “Zero Electric Bill”: The customer’s goal is to replace all of their electric bill down to zero payment to the utility. It’s a bit of a misnomer, the utility will always have a “interconnection charge” which is typically between $5 and $12/month, depending on the ulitilty rate seleted post project. This Zero Electric Bill option will have the longest payback time, but also the highest total return on investment. Some customers choose this option because of their “green tendancies”, or because they have the cash and “just don’t want to pay for any electricity from the utility.”
I have heard of peak power shaving by solar systems; what is it?
Solar panels generate peak power when electricity demand is at its highest and most expensive (midday). Using a time-of-use tariff and under Net Energy Metering, homeowners are able to produce and sell electricity back to the utility at high rates (midday) and purchase electricity back at low rates (evening). For a more detailed description on Net Energy Metering (NEM) visit our How it Works page.
Can I power my home with solar when the grid goes down?
Solar installations offer partial protection against grid failure, particularly if (battery) storage capacity is also located on site. Learn more about the energy storage market here.
Money
How long before a solar system investment pays off? What returns can I expect?
The solar systems we install typically have a payback period of five to seven years. Considering the system will generate electricity for 30 years, an Internal Rate of Return (IRR) of 15% is not unusual. A $15,000 investment in solar could save you over $150,000.
What rebates can I get?
The main incentive that all tax paying Americans qualify for is the 30% Federal Investment Tax Credit that will be available until December 31, 2019. See detailed Federal 30% Tax Credit info here.
After December 31, 2019, the 30% Federal Investment Tax Credit (ITC) will step down to 26% for the year 2020, 22% in 2021, and 10% in 2022. As it stands, homeowners will no longer be able to take advantage of the Investment Tax Credit after 2022 unless the Federal Government agrees to extend or amend the ITC like they did in 2015. See the below graphic.
*Graphic by SolarPowerRocks.com
Technology
What is solar electric/photovoltaic (PV) power?
Solar electric or photovoltaic (PV) power is a term used to describe the process of converting sunlight into electricity using solar cells. These cells are constructed from semiconductor materials and are grouped together to form a solar module. Modules are typically enclosed in a glass to protect them from the elements and mounted in a frame to provide strength and a means of attachment. Most home systems consist of 10-30 modules connected together to form the solar PV system.
How do solar cells work?
Solar cells are (semiconductor) solid-state devices (no mechanical action) in which photons (or packets of light) collide with atoms transforming the resulting energy into electrons. These electrons flow into wires that connect all the individual cells in a module and all the modules in a system.
What happens to electricity flowing from the solar PV system?
The electric current that flows from the solar PV system passes through an inverter which converts the direct current (DC) to alternating current (AC); the type of electrical energy used in the home.
What components make up a complete solar (PV) system?
A Solar PV system typically consists of solar panels, an inverter (to convert electric power from DC to AC), wiring (to collect the electricity from each of the panels and feed it to the inverter and meter), mechanical support structure (to hold and attach the panels) and an electric utility meter (to measure the performance of the system).
Why does my solar array cease powering my home or business when the utility grid goes down?
Consider the fact that you can’t really control the output of your solar power whether the grid is operational or not. The power output of the solar array is dependent on the amount of sun’s rays impacting it. If your home is consuming all the power when connected to the grid, the extra power goes to the grid. If the grid is down, the inverters auto shutdown to prevent “islanding”. If a solar array were allowed to produce it’s own power while connected to the grid, any excess power travels to the grid. When the grid is non-operational, it’s safe to assume that utility personnel may be working on the grid in order to repair it. It’s necessary when the utility personnel work on the grid, the utility lines are unpowered for their protection. Therefore, in order to protect utility workers, solar systems are not allowed to operate interconnected to the grid when the grid is down. For a solar system to continue to operate during grid outages, they need to be “bimodal” systems. To properly accept excess power from a solar array, when attached to the grid, the grid accepts that power. The grid acts as a “battery”. In the absence of a grid connection, a real battery bank has to be available for acceptance of the excess power, or to provide additional power when the electricity provided by the solar array is not sufficient. Without a battery bank, a solar array can not operate properly without potentially causing damage to the equipment it is powering because of the inability of the equipment to self regulate it’s electric output. A “bimodal” system that will operate without utility interconnection has additional equipment to regulate power output such as charge controllers, batteries, and a critical load panel. Bimodal systems are much more expensive than utility interactive systems because of this additional equipment.
Is it possible to include a breaker or manual flip switch of some sort that would allow me to continue to generate and use power from the cells if it were not available from the grid? (Let’s say, in the event of a massive earthquake.)
There are multiple answers to this question. To continue to provide power in the case of utility outage, a solar system must be designed as a bi-modal system, as described in the previous question. Back up power in the case of a grid outage (especially for long periods of time) is a very valid concern. Generators are a good, relatively inexpensive solution. However, fueling that generator for the long term (potentially over the course of weeks or months in the case of a very serious outage) will ultimately be expensive, and perhaps the fuel itself will become hard to come by. There are solar rechargeable generators that are worthy of investigation. Very simply, depending on it’s storage capacity and output, it can be a relatively small unit. These solar rechargeable generators consist of a couple of small solar panels, batteries, a charge controller and an inverter. These units allow the plugging in of standard household items for critical loads such as refrigeration, medical equipment, etc. These systems are “stand alone, charge controlled solar PV systems” and are available on the EBay and Amazon websites, amongst others.
Does temperature affect solar PV panels?
Yes – solar panels work more efficiently in cooler weather although they are designed to withstand the harshest summer conditions. High (altitude) desert regions are optimal.
How long will solar panels last?
Quality Tier 1 solar panels such as those from Silfab Solar and LG Solar will last over 25 years. In fact, Silfab Solar (Go Simple Solar’s preferred Buy American Act certified module) has recently extended its product warranty to 25 years and power output guarantee to 30 years based on favorable product testing combined with more than 30 years of actual module performance in the field. Panels that are not quality made will fail well before this; a study was conducted by DuPont Labratories which determined that the seal between the frame and the solar cells will fail in cheap solar panels at about year 12; making them much less efficient and reducing their life significantly.
What is solar irradiance testing?
Irradiance refers to the power of solar radiation per unit area on a surface. Global irradiance on a horizontal surface is comprised of direct irradiance and diffuse irradiance. On a tilted surface, the reflected irradiance from the ground also contributes to the total global irradiance. Generally, solar irradiance is called insolation.
Solar radiation affects many systems in the house and can vary considerably within the same town. On-site, solar irradiance is a particularly useful measurement if there is a photovoltaic (PV) system or solar thermal system installed at the field test location. Also, if space conditioning is a focus of the field test, solar irradiance is an important measurement as solar radiation has a large effect on heating and cooling load requirements, electrical lighting demand (daylighting), and envelope performance.
Compliments of NREL.gov
Installation
How long does it take to install a system?
It will typically take 3-5 days to fully prepare a site and install the system, depending on size and installation type. On most residential projects the whole project will be complete in 3 days, with building permit sign off from the local municipality on the 4th day.
Where should the solar PV system be placed?
Ideally, the solar panels should be mounted on a roof, building or piece of land, where the panels have maximum amount of unobstructed sunlight. This is typically on a tilted, south facing surface where the solar panel is perpendicular to sunlight.
Are there any concerns with the age of a roof when installing solar?
Because our solar systems are guaranteed for 25 years you wouldn’t want to install one on a roof older than 30 years. If you want to re-roof before installing your system, we have a team of licensed roofers that guarantee their work for life. Another option is to re-roof the section of roof under the solar system and re-roof the rest later on.
Q & A
I think you mentioned that you are against change orders. Do you refund the $1000 deposit if your site visit turns up significant issues? Or am I SOL?
We’re not against change orders, We’re against the totally illegal rampant practice of contractors unilaterally changing their price after a contract is signed. If you give us a $1000 down payment and we find something that changes the price AFTER starting work, it’s OUR loss. We earn our reputation by making customers happy, not keeping deposits. Keeping your money would be illegal for starters. A customer ALWAYS has a three day right to cancel. After a site visit the only way a price changes is if there are circumstances or site conditions that would raise the cost that we couldn’t have reasonably discovered; hidden damages, mold, electric wiring problems not visible until construction begins, etc. That may cause a price change. Please see the documents attached for an average job. We’re extremely diligent in planning and execution, and we have had NO surprises that have caused price changes to the customers. Sometimes we find SMALL things that WE should have been able to PLAN, but WE eat the small costs associated with those items. If the customer wants something changed, that may trigger a change order, but that’s at customer request, not contractor unilateral price increase. We don’t have the reviews and customer satisfaction we have from being anything other than… well, pretty much perfect.
I’m intrigued by your choice of solar panel manufacturers like Silfab Solar and LG Solar panels – Why do you prefer them over companies like Jinko, JA, or GCL?
Go Simple Solar believes in installing the highest quality, domestically manufactured equipment for all residential and commercial Solar PV installations. For this reason, we choose to stay away from solar panels and other products made by the above mentioned companies. In the past, Go Simple Solar exclusively used SolarWorld panels. After SunPower’s acquisition of SolarWorld, we now use Silfab Solar (based in Toronto, Canada and now manufacturing panels in both Canada and Bellingham, Washington) and LG Solar (now manufacturing Neon2 panels in Huntsville, Alabama). We may lose business to lower cost and cheaper quality Chinese panels, but that’s not the business we want anyway…People value our approach – USA made products installed by licensed electricians/roof installers, and rabid customer service. We’re proud to offer products we know will measure up to product warranties, output guarantees, and the lowest field tested defect rates in the industry.
Why have you planned for only a 59% energy offset? Seems like I would want more. What would a 20 panel proposal (vs. 16) look like? Or how hard is it to add future panels?
Every other contractor tries to sell you as many panels as they can. Our approach it to right size if from a “quickest payback” perspective. The dialogue about size begins here. If you want more, then you want more. That’s your decision. Solar is a financial decision, and going bigger slows down the payback time a bit, but also increases the long term returns. Solar is about bill cost offset, not energy offset. With this size system, the software shows a 77% bill reduction, that’s the important part. That’s the sweet spot of size I’m talking about. Easy to add future panels with the micro-inverters, you just have to tell us in advance to run an extra circuit, and all the additional work can be performed on the roof, and not down to the electric panel. 17 of these modules can fit on one circuit, after that, 2 is required for up to 34 modules. An extra circuit costs $350. Many customers choose this option for potential upsizing/future electric car, etc.
I’m a Danville resident looking into rooftop solar and liked what I read and saw online. I have concerns about solar panel survivability and therefore the value of many company’s 25-year warranty. Can you relieve me of that worry?
“Thanks for checking in.
I think you have a valid concerns. I have concerns about any company involved in the solar business right now.
One of the biggest inverter companies recently went out of business, the world’s biggest module maker is bankrupt (Suntech, not that I’d ever install a Chinese module anyway) and Sunpower is owned by the French oil company, Total. Chevron, Mobil and others such as Chevron closed down their solar divisions after purchasing them.
We choose Silfab Solar and LG Solar because in these uncertain times, the best warranty is an excellent product. Silfab Solar has more than 35 years of product performance history, and there’s very few people today that don’t know the name LG – who have been manufacturing electronics for over 70 years. Durability and performance history trump any theoretical “bankability” of a company. That being said, Silfab Solar and LG Solar both offer 25 year product warranties in addition to industry-leading low defect rates.
This is how we came to arrive at the comfort level of using these products. Very importantly, it’s American made. If we can do it the best with USA products, we always will.
If you would like a proposal, please let me know. You can fill out the form at www.GoSimpleSolar.com/quote.html
If you would like to consider other products to install, the only other one I would consider is Panasonic and Mission Solar. Place of manufacturer and product performance history are most important.
We won’t install anything Chinese, the reason is that the warranty claims are suppressed by agreements between the manufacturer and the warranted person. There is no transparency in those products, the failure rate is well known, it’s just not allowed to be specifically tagged to the individual companies because of those agreements. It’s our business decision not to install modules that may have callback problems, not good for the customer OR the business!”
– Mark Becker, President