Ask yourself the following questions before you install solar panels.
1. Is your roof even suitable to support the solar panels?
Consider this one, first and foremost. If, for most of the day, the beautiful trees on your compound throw shade on your roof, the solar window may not be enough for ample solar energy collection. Sure enough, your panels would collect some, but will the little energy collected justify the money you put in for the full installation?
If your roof is not suitable, you do not have to give up on solar power. You could always look into shared solar energy or community solar. It may not indeed appeal to you, but this sort of approach allows you, along with multiple other consumers, to purchase a stake in some solar installation. Of course, you would have to deal with a small bill at the end of the month.
If your roof is all right for solar panel installation, make sure that it is strong enough. Consider renovation if the roof’s shape is not as good as it should be. If you have to conduct revisions on your roof a few years down the line, it would cost you money to have the solar panels disconnected, and then set up again.
Do not forget to read any homeowners association “covenant” as well. Some of these prohibit such additions as solar panels to rooftops. It is, for the most part, an aesthetics thing, but you would have to abide by it nonetheless.
2. Can you say you have done all you can to maximize efficiency?
Put simply, the solar energy amount that you intend to produce would depend on the energy you use. It makes all the sense in the world to trim your energy use as much as you can. Perform an energy audit at your home, install as many energy efficiency upgrades as you can and then think about drawing up those solar energy blueprints you are so itchy to draw up.
3.Which solar kind makes the most sense?
There are two dominant solar energy technologies to choose from: photovoltaic technology, which employs cell arrays to convert sunlight to electricity, and thermal technology, which uses sunlight to heat up water, even air, for use inside.
If you have known your home to use lots of energy, especially for heating, or you live in the sort of place that comes with high heating fuel bill, meaning an investment in solar thermal technology could save you much money going forward. However, there is a reason why you perhaps did not know there were two solar energy technologies: very few people ever have solar thermal technology installed in their homes. This information deficit means that you may have a much harder time installing this technology. If you decide to go for a qualified installer, then you may end up throwing a lot of dollars at him, or her.
4. How will you be able to connect to the grid?
Details tend to vary going by where you live. Still, any time you connect with a utility, there is more than a few logistics to wade through. Is there a fee to be paid? How long will it take you and yours to get hooked up to the grid? Once you do get accredited, how will you get credited for the power you are generating? When will this happen?
If you have no idea what those last two sentences allude to, they are referring to net metering. Utilities are supposed to reimburse solar at about the same rate they charge electricity users. Before you start beaming, understand that this particular area is rife with political shenanigans. Look at the state of Nevada, for instance, which has policies in place that reimburses peanut amounts, making it difficult to recoup installation costs. No matter which part of the US you live, you get refunded for sure if you connect to the grid: however don’t get your hopes up too much.
5. If you employ the services of an installer, can you trust him or her?
The issue of trustworthiness, in all honesty, applies every time you have professionals or other come into your home. However, when you consider that solar tends to combine home improvement logistics with electrical risks, you need to be a lot more careful here. Insist on credentials and make sure they are valid. As a smart man once said, “What sense does it make to hire an electrician who has never done actual electrical work?”
Having answers to the questions above in mind, now you can begin getting a bit technical with solar power installation. Let’s start by learning the Mechanisms Of Solar Panels because it is the core of installing solar power.
Mechanisms Of Solar Panels
It helps to understand how solar panels work, even as you seek to install one. While the solar panels sale appears to be something mystic- an assemblage of sophisticated technologies, it is pretty simple. Once you understand the concept of solar cells and how they work, you well along your way to understanding the solar panel’s workings. However, first, let us lay some ground before attacking the solar cell subject. How much energy can we realistically get from the sun?
Here is some technical information that, while not being too vital in the general scheme of things, gives you some perspective on just how much energy the sun has to offer. Every square meter of the earth’s surface gets up to 164 watts of energy from the sun. Look at it this way: you could set up a very potent table lamp (say, a 150-watt lamp) on every square meter and pretty much illuminate all of the earth using solar power. This is quite impressive, is it not? However, if this looks a little too fancy to digest, then consider this other example: if just 1% of the Sahara desert were to be covered with solar panels, the solar energy produced would be sufficient to power the entire world. What I am saying is simple; there is an awful lot of the sun’s energy to go around!
However, this energy cannot be directly used. It has to be converted to electricity.
Understanding solar cells
A solar cell is a device that traps sunlight and directly converts it to electricity. A solar cell is about the size of your palm. Its shape resembles that of an octagon, and its color is bluish-black, which is why all solar panels tend to have the same bluish-black tint to them.
On its own, a solar cell is not much use; you could not derive enough electricity from it. Solar cells are usually bundled together to form larger electrical units known as solar modules. These modules are themselves bundled together to form even larger electrical units that the world refers to as solar panels. At times, they are “chopped” into portable chips so they can power small-sized electronics, such as pocket watches and calculators.
Comparing the solar cell to a solar battery
Like is the case with the solar battery, a solar cell in your solar panel was designed so that its primary function is to generate electricity. However, whereas the solar battery derives its electricity from chemicals, the solar cell captures sunlight, which it converts to electricity. Some people insist on referring to the solar cell as a photovoltaic cell given that they use sunlight (the Greek word for light is ‘photo.’ As for the “voltaic” bit, it refers to Alessandro Volta, the legendary Italian electrical scientist.)
The way of the solar cell
Think of light as being comprised of small-sized particles called photons. With this in mind, a light beam is akin to a brightly colored fire “hose” that shoots trillions of photons toward the Earth. When you place a solar cell into the beam’s path, it traps these photons and proceeds to convert them from a flow of photons to a flow of electrons. In short, it converts them to electrical current flow.
Each cell generates a few volts, so the panel’s job is to bring together all the electricity produced by the individual cells so that the current produced is large enough as to be useful. Most solar cells consist of silicon slices. When sunlight hits a solar cell, the energy it carries then “blasts” electrons contained in the silicon. These electrons are directed through an electric circuit and power gadgets that use electricity to run.
How are solar cells constructed?
We said that solar cells comprise of silicon. Silicon is a semiconductor: it does not typically conduct electricity, but under unique circumstances, it can.
A solar cell is essentially a two-layer silicon sandwich, where the silicon is specially treated to allow electricity indeed to flow through it uniquely. The lower silicon layer is treated so that it has “slightly too few number of electrons.” The upper layer is treated oppositely however so that it has slightly “too many electrons.”
When you place a layer of the latter on a sheet of the former, a wall forms at the junction. No electrons can pass this barrier. However, this ceases to be the case when light shines on this silicon sandwich. As the photons, or light particles, enter the silicon sandwich, they “give up” the energy they carry to the silicon atoms. This incoming energy blasts electrons out of the lower layer so that they leap across the barrier to the top layer and then flow out and around the electrical circuit. The more light shone, the higher the number of electrons that are knocked off, and the larger the current derived. Scientists like to refer to this phenomenon as the photoelectric effect.
How efficient are solar cells?
If you attended grade school science lessons, you are familiar with the scientific claim that it is impossible to create energy. You can only convert energy from one form to the other. Thus, a solar cell cannot put out any more power than it gets from the sun. Even more importantly, it is impossible for the solar cell to give out just as much energy as it gets from the sun; a fair amount of it gets lost in transition. In practice, solar cells are only able to convert 10-20% of the energy they receive from the sun. A single injunction solar cell, however, has a maximum efficiency of around 30%. So before you get intimidated by the “single injunction” tag, this sort of cell is the typical cell in your solar panel.
Now that you know how solar panels work and understand the different terms you may come across in the book, let’s look at batteries.
Choosing Batteries: Lead Acid or lithium iron phosphate batteries?
What is the superior battery type?
So very many off-grid energy systems have dead lead acid batteries around the US that a documentary covering all of them would run for years before exhausting them all. Moreover, it is difficult to blame the door of the lead-acid batteries: they are designed to work for a few years, which is what they do before fading and losing their charge depth. Lithium-ion batteries, on the other hand, while considerably more complicated than their lead counterparts, have some notable advantages. There is no argument that lithium batteries are superior. Let us examine exactly why this is so:
Lithium versus Lead Battery
Lithium-ion battery
Advantage #1: The size and weight of the lithium battery are superior Lithium batteries are a lot smaller than a lead battery. In fact, lithium batteries are only a third the size and weight of the typical lead battery. The charge capacity is similar to that of the lead battery, something made possible by the lithium battery’s superior energy density. The higher energy density improves deployment and installation to a considerable degree.
Advantage #2: The resilience level of Lithium is better than Lead As you may well know, all batteries may be quickly and extensively damaged when excessively discharged. The same is the case when the battery is stored at extreme temperatures. However, the lead battery is a lot less tolerating of this roughhousing and is inevitably damaged when repeatedly discharged too quickly. If the lead battery is discharged below half its State of Charge (SOC) or discharged faster than C/8A (C8 rating means the battery is completely discharged over a period of 8 hours), it loses potential cycles.
Compare this to the lithium battery: it could be discharged to up to 80% of its SOC and at a high C/2 rate(C/2 rating means the battery gets wholly discharged over a period of 2 hours), and there is no long-term damage to show for it. If you have no plans to keep changing batteries every few years while having to be super careful with them, the lithium battery is the ideal option.
Advantage #3: The lifecycle is superior
Let us talk battery prices. It is no secret that the lithium battery costs you a lot more dollars than the lead battery. With time, this will change, and the lithium battery will cost a lot less (projections say that in a few years, prices will drop below $400 per kWh). As is the case with many things, a lower price for a particular product (Lead battery)compared to another(Lithium battery) does not always make it cheaper. Some wise fellow once said “cheap is expensive”: this is what we are alluding to.
Look at it this way: a lead battery, while costing less, will require lots of maintenance and you will surely have to replace it after some time. A lithium battery, while costing more, requires minimal maintenance; it is a lot more tolerant to rough treatment and has a lifespan equaling that of, say, 3-4 lead batteries.
What do you do at this stage?
The 12v lithium battery is undoubtedly the better battery. Still, the lead battery has served the world for nearly two centuries, so it cannot be vilified. If money is a problem, start out with the lead battery, while looking to move to the lithium battery in the future.