How Much Solar Do I Need?
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How much solar you need for your home is actually a far more complicated question than you might think. There are a plethora of variables that go into calculating your solar needs; this post outlines a few of the major ones.
Factors That Impact How Many Solar Panels Your Home Needs
Most people that call to learn more about the price of solar expect a straight forward answer. A person might stay that they use 1,000 kilowatt-hours of power each month and expect a quote on the spot.
This, however, is not the only factor that is used when determining how many solar panels you will need. And this approach to getting the solar appointment is beyond the scope of persuasion techniques or psychology – it actually unfolds this way because it needs to, from a structural standpoint. First, let’s take a look at the role your monthly kilowatt-hours or usage has in forming a quote.
How Your Home’s Usage Applies to Solar Quotes
Every home is different and it is therefore impossible to give an across-the-board quote. You may have a large home, renters in the basement, or have little to no insulation.
All of these factors would affect your home’s energy consumption. However, when you look at your energy usage over the course of a year, you can get a more accurate estimate of your home’s energy needs.
Knowing how much energy you typically use in a month is the first step. You then need to determine if your home is a good candidate for solar.
Why Shading and Roof Pitch Matter for Solar Production
In the beginning stages of creating a solar proposal, a Google image of your home is rendered. From this image, software is used to determine off-the-panel factors such as the pitch of your home’s roof, as well as on-the-panel factors such as azimuth needed for the solar panels themselves.
This allows the installer to determine which type of mount will be best for your situation. Which mount you use can affect the overall cost of your system.
Types of Solar Panel Mounts
Since every home is different, this means that several mounting types are available. Which one you will need is dependent on the type of roof you have and your average electricity usage.
The Most Common Solar Installation Type: Roof Mount
The most common installation type is the roof mount. This is when the solar panels are mounted directly to the roof of your home. There are three main types of roof mounts — on-roof, in-roof, and solar tiles.
On-roof systems are the most common solar installation type. In this kind of mount, the solar panels are bolted onto the existing roof.
An in-roof system is best for homes installing solar while building their home. These systems are seamlessly installed into the roof rather than on top of it.
Solar tiles produce solar without taking away from the look of your home. Solar tiles are also best for homes that are currently building their home. They are also a viable option if you are about to re-shingle your roof.
If you have a flat roof, you will need to consider a different solar mount. This is because a flat roof doesn’t have any pitch.
When It’s Ideal To Use a Ballasted Solar Mount
Because flat roofs do not have any pitch, ballasted mounts are often used to hold the solar panels down. With a ballasted mount cement blocks hold down the solar panels instead of bolts.
If you don’t have enough non-shaded space on your roof for a solar array, you may have to consider a different solution. One option is installing a ground mount.
Optimal Scenarios for a Solar Ground Mount
Ground mounts are generally about three to four feet off of the ground. They also require a large amount of non-shaded space. The specifics of how much space is needed, however, depends on the area in which you live. When you receive your free customized solar quote these standards will be taken into account.
When a Pole Mount Is a Good Option
A pole mount is taller than a ground mount. Some of them even have the ability to move the panel to an optimal position to absorb maximum energy from the sun depending on the season. Normally, however, residential installations don’t use a pole mount. They are more common among rural commercial solar projects or solar farms.
Once you have determined the type of mount that is best for your solar needs, the next logical step is to consider the type of solar panel. There are several solar panel manufacturers and solar panel types out there. Deciding which one to use can be tricky.
Types of Panels and Their Efficiency Ratings
Because photovoltaic technology is still emerging, there are lots of different options. Let’s take a look at the most well-known and used solar panel tech.
What Makes Monocrystalline Solar Panels the Best
Monocrystalline is the most widely accepted solar technology. It is also the oldest and most developed solar tech. These solar panels use pure silicon crystal to form the solar wafers within each solar cell of the solar panel. This is done by creating ingots which are then cut into thin wafers.
You can often tell by the darker uniform coloring of the panel that it is mono-crystalline. Their efficiency ratings are normally between 15 and 20 percent.
They are also known for their higher wattage. Many mono-crystalline panels can get up to 300 watts and some can reach 350 watts. This means that these panels are not only efficient, but you don’t need as many of them to meet your energy production needs.
Reviewing Polycrystalline Solar Panels
Polycrystalline solar panels are known for their blue hue. Fragments of silicon are melted together to form an ingot which is then cut into wafers used in the panel.
Because of the fragmented silicon, these panels are less efficient. They often have between 15 to 17 percent efficiency ratings. They also usually have lower wattage ratings; it is uncommon for them to reach 300 watts.
This means that although they are cheaper in terms of per panel price, you will need more of them to meet your energy production needs, especially if your electricity usage is high.
Taking a Look at Solar Shingles
Solar shingles blend into your roof. Each mini panel has an area of a couple of feet. When installed these are then reduced to an even small space for sunlight to hit.
It is unknown how efficient these mini panels are. The Tesla shingles are supposedly using Panasonic technology.
Currently, Panasonic has efficiencies up to 20 percent. However, because these solar panels are so small, the wattage that each panel will produce is not very high. This means that the expense to have solar shingles installed is quite high.
Current Types of Thin Film Solar Panels
Thin-film solar panels can be made from a variety of different materials. To create a thin-film solar panel you need to put one or more thin layers of photovoltaic material on a substrate. Common substrates include plastic, glass, and metal.
The efficiency of these solar panels is normally close to 11 percent. Per square foot, these panels typically produce less energy than both polycrystalline and monocrystalline technologies. This means that, although the solar panels will be lighter, you will need quite a bit more space.
Outside Forces That Determine How Much Solar Power You Need
Now that you know the controlled factors in solar production, it’s logical to look at outside factors. The average weather in your area plays a role in how much solar you need to meet your energy needs.
The Seasons’ Effect on Solar Production
Where you live makes a difference. This is most easily seen in peak sun hours. These are the hours on an average day that your area will get optimal sun exposure. These hours, however, change during the year.
Although your peak sun-hours could be five hours, it will be less during seasons when the sun is hardly out and more during hot summer months.
To determine how much solar your home needs, designers find the typical sun exposure of your area. This is then used to determine how many solar panels are needed.
Efficiency of Solar With and Without Battery Backup
Although weather is relatively predictable, it is not always consistent in relation to solar panels’ production. To deal with this dilemma, many have connected their solar arrays to the grid. This allows them to draw power when their system isn’t producing.
Although a great concept, it can cut savings. Net metering allows solar customers connected to the grid to sell their excess generation. However, this is often at a lower rate than they pay for the energy pulled off the grid.
Net metering still saves customers money on their energy bill. This is why so many people are doing it. However, it does cut into some of the savings generated by your solar array.
This may seem like a dismal dilemma, but with backup, you are able to store your energy for later use. Depending on the size of backup you install you could power essentials or your whole home.
Using Solar Power Calculators to Predict Solar Needs
Although the first step when looking for solar, it is the last in this post. This is because solar calculators are generally the least accurate way to determine your solar needs. Let’s take a look a why and how to use them as a starting point.
Optimizing Google’s Project Sunroof
Google’s solar calculator gives you an idea of whether your home is a good candidate. It also gives basic solar costs in your area.
This tool is great for determining a baseline but it doesn’t tell you what you actually need. You still need to compare several solar quotes to determine this and more accurate usage and azimuth levels.
How to Use Solar Installer’s Calculators
Many solar companies have their own solar calculators. This is a great way to determine possible savings, but again it isn’t specific. This is a baseline to work from.
Once you have determined what the baseline price in your area is, it is time to do some shopping around. Customers that take the time to look at several companies, both large and small, save more. As a result, they are also happier with their solar company and installed array.