Here’s a list of everything you’ll need for an off-grid solar system to work:
- Charge controller for solar panels
- Inverter for solar power (s)
- System for mounting and racking
The charge controller sends the electricity from the solar array to the battery for storage or to the DC-AC converter (also known as an inverter) to give power to the home.
Watch this video to hear from Will White, a solar specialist with first-hand knowledge, about what it’s like to live off the grid.
What does an off-grid solar system entail?
Solar panels, charger controller, inverter, and battery bank are the four essential components of most DC-coupled off-grid systems. There’s a lot more to a solar system than that, but those are the four basic components that will be described in this essay.
Solar Panels & Mounting
The solar panels are the most visible component of an off-grid solar installation. Solar panels with 60, 72, 120, 132, or 144 cells are currently the most cost-effective. The little squares that make up the full panel are called solar cells. Monocrystalline panels are now the industry standard in the majority of installations.
A standard 60 cell monocrystalline solar panel measures roughly 68 40 inches and produces 300-375 watts, whereas a 72 or 144 cell panel measures around 80 x 40 inches and produces 375 watts or more. One of the most important computations in Off-Grid system design is determining the size of the solar array.
The suitable array configuration is then determined. The solar panels are connected in series strings (limited by the maximum input voltage), and then the different strings of solar panels can be connected in parallel to form a large array (limited by power or current). This technology reduces the output of a solar array to as few conductors as possible.
So, why monocrystalline panels rather than polycrystalline ones? It all boils down to cost and availability. Monocrystalline panels are commonly utilized in off-grid solar systems, as the industry has turned to producing low-cost monocrystalline modules. Because polycrystalline panels were less expensive to manufacture in the beginning, they had an advantage. Monocrystalline has now become widespread, far more efficient, and affordable, therefore there is no longer a compelling need to use polycrystalline.
There are three main installation methods for solar modules, with the choice usually based on the application or available mounting space:
Roof Mount Installing a solar array on the roof of a house or other structure.
Parallel rails are secured to the roof system with feet secured to roof trusses or cross members, and solar panels are placed on top of these rails and secured with a clamp mechanism. Solar panels mounted on the roof have the advantage of utilizing an existing flat roof space. Roof mounts have the drawback of not optimizing the solar panel angle in reference to the southern horizon, lowering the array’s potential energy production.
The solar array is mounted on a pole that is concreted into the ground.
A gimbal is mounted to the top of a vertical steel pipe at the top of pole mounts. The solar panels are then mounted to the gimbal through a series of rails. A single panel can be attached to as many as 12 solar panels on a single pole using the top of pole mounts. The solar panels can be tilted appropriately from perfectly horizontal to 45 degrees using these mounts. Top pole installations are easier to clean because they don’t require climbing a roof, and they also shed snow effectively.
- Ground Mount – For further stability, the solar array is mounted on concrete piers that are closer to the ground.
A lattice of vertical and horizontal steel poles with parallel rails, usually aluminum, is used in linear ground mounts. The solar panels are then fastened to the parallel metal rails. The panels are organized in a row and column pattern, with the complete array inclined towards the southern horizon for maximum energy generation. Linear ground mounts are easier to clean than top-of-pole mounts and are also easier to clear of snow than roof-mounted arrays. The primary limitation to using linear ground mounts for large solar arrays is the amount of accessible ground space.
The charge controller is the device that controls how much energy is sent from the solar panels to the battery. Charge controllers ensure that batteries are correctly charged and not overcharged, which is critical for the battery bank’s longevity. MPPT (Maximum Power Point Tracking) and PWM (Pulse Width Modulation) are the two major forms of charge controllers (Pulse Width Modulation).
MPPT charge controllers are distinct in that the input voltage from the solar panels must be 30% higher than the battery voltage (up to the charge controller’s limit), so it doesn’t matter what voltage solar panels are utilized with the system.
MPPT charge controllers are more efficient because they can track and deliver the maximum amount of electricity from the solar panels to the batteries. For the same amount of power, it converts a higher voltage/lower current input to a lower voltage/higher current output. Given this, MPPTs can precisely manage the amount of power transferred to the batteries, which is critical when the batteries are full and trying to meet system demands. The key benefit of employing an MPPT controller is that it can capture the greatest power from the solar array at any given time, as opposed to a PWM controller’s limited input. A PWM can supply the same amount of power as an MPPT, but it will never be more powerful than an MPPT. As a result, MPPTs are typically the standard when selecting a charge controller for a solar system.
Pulse modulation is used by PWM charge controllers to turn on and off the rate at which energy from solar panels is supplied to the batteries. The nominal voltage of the panels must match the nominal voltage of the batteries when using PWM charge controllers. If the system uses 12 volt panels, for example, the battery bank must also be 12 volts. There isn’t much control over how the power from the panels is managed using a PWM; it’s just pouring it into the batteries. In comparison to an MPPT controller, PWMs have restricted input.
An inverter is the next component in an off-grid solar system’s architecture. The inverter in nearly all off-grid solar systems is a battery-based inverter. The inverter’s job is to convert DC electricity stored in the battery bank into usable AC power and transfer it to your loads in the same way that you would plug into an AC outlet in your house. Depending on the off-grid loads required, inverters come in a variety of sizes that can serve smaller or higher loads. Another factor to examine is if the inverter can manage all of the loads in the system at the same time.
When all of the system loads in the off-grid system are totaled up, the maximum amount the inverter must be able to handle is determined. To learn how to determine system loads, watch the video below.
Our team will be able to develop a system that can manage all of the loads required if they learn how to compute the system loads for a specific system.
Another crucial point to remember is that the inverter must be matched “The system in which it is employed in terms of voltage. A 12-volt inverter, for example, cannot be utilized with a 24-volt battery bank. It requires a 12-volt battery bank to operate. Unlike charge controllers, an inverter’s voltage cannot be adjusted because it is fixed and must match the system’s battery voltage.
Given this knowledge, it’s critical to select an inverter carefully when constructing a system, especially if expansion is in the works. Choosing an inverter is an important decision to make early on in the planning phase.
Inverter chargers are used in most off-grid installations. Notice how we used the word inverter “a charger So far, we’ve learned what a standard inverter performs. What is the purpose of an inverter charger? The inverter charger performs the same functions as a standard inverter while also serving as a charger. That is to say, the inverter not only has an output but also an input.
This is significant because it allows the system to employ an external power source, such as a gas generator, to power system loads rather than relying on the battery bank. After the system loads have been satisfied, the extra power from the external power source is used to charge the battery bank. Using an inverter charger provides system redundancy, which is necessary if there are numerous overcast days and the solar array is unable to charge the battery bank.
Hybrid Inverter System
The majority of hybrid inverters are all-in-one systems, which means they have inputs for solar, grid, loads, generator, and batteries. For a highly customized and versatile solution, a hybrid inverter system combines the advantages of both the MPPT charge controller and the inverter/charger worlds. Hybrid inverters or ESS – energy storage system – are the terms used to describe these types of systems. Hybrid inverters are frequently utilized in applications that require a simple, easy-to-install, all-inclusive device. Like a charge controller, they can regulate PV production and battery charging, but they can also supply power output from batteries and/or PV, just like an off-grid inverter. Hybrid systems are often the ideal choice for flexible and dynamic solutions due to their flexibility. These solutions, which are also relatively current, function extremely well with lithium battery solutions. Most will also allow you to use a generator to charge your batteries (or Grid where applicable).
The battery bank is the final major component of a solar system, and it is both one of the most vital and one of the most expensive. There are two common battery chemistries in the solar power industry: lead acid and lithium.
The chemistry of most lithium batteries used in the solar power sector is Lithium Iron Phosphate (LiFePO4). Lithium batteries differ from flooded lead-acid and AGM batteries in a number of respects, including size and weight, as well as how they can be charged and discharged. Lithium Iron Phosphate is a very safe chemical because it does not off-gas and may be stored without needing to be ventilated. Unlike lead-acid batteries, lithium batteries require no maintenance and do not need to be fully charged. The LiFePO4 chemistry was also created with a large number of charging cycles in mind. Because of these properties, lithium batteries are ideal for off-grid solar applications. Another benefit of lithium batteries is that they include a built-in battery management system (BMS) (battery management system). The battery’s working state is constantly monitored by the BMS. This means that if the battery is overcharged or is too hot or cold, the BMS will compel the battery to shut down until the parameter violations are corrected. Consider BMS to be a layer of safety for your batteries, making it more difficult to destroy them.
Another benefit of lithium is that it may be stacked or expanded without impacting the life of an existing battery bank. Adding batteries to an existing lead acid battery bank will cause the entire battery bank to die prematurely. Lithium batteries are also available in 12v, 24v, and 48v versions, allowing them to be easily paralleled with standard system voltages. This is significant because if the BMS forces a battery into shutdown mode, the entire bank does not have to shut down.
Lithium batteries are far superior to lead acid batteries in every way. In the long run, the depth of discharge, the number of charge cycles, safe chemistry, and a built-in BMS deal a fatal blow to lead acid batteries. Not to mention that lithium batteries charge faster and can continuously offer a significant amount of power without causing damage to the battery. Furthermore, all reputable manufacturers offer lithium battery warranties of roughly 10 years, which is significantly longer than lead acid battery warranties. Another advantage is that a lithium battery bank requires far less space and weight than a lead acid battery bank.
Floating lead acid batteries and sealed AGM batteries are the two major types of lead acid batteries used in solar.
A flooded battery is a normal wet cell lead acid battery that is typically the most cost-effective battery in the beginning. The batteries themselves are quite affordable, but they do require routine maintenance to ensure that they last as long as possible. To keep the battery from being destroyed, routine maintenance is required, such as checking the water level in the battery and testing the specific gravity. Regular equalization charges should also be performed to prevent stratification of the electrolyte and to loosen any build-up that has hardened and clung to the battery’s plates. Off-gassing is another factor to consider when using flooded lead-acid batteries. When lead acid batteries are charged under specific conditions, hydrogen gas is created as a byproduct, necessitating battery bank ventilation. When dealing with hydrogen gas emissions, a lack of ventilation might be deadly, so it must be addressed carefully. Many individuals like to utilize these types of batteries for their solar applications since they are cost-effective. Premature lead acid battery failure is frequently caused by a lack of maintenance or heavy usage. AGM batteries may be the ideal choice if you want a maintenance-free battery with a cost-effective lead-acid option.
AGM stands for Absorbed Glass Mat, which refers to the fiberglass mats that run between the plates and absorb the electrolyte. These batteries are totally sealed, and they require very little maintenance. AGM batteries have the same life expectancy, charge cycles, and size/weight as flooded lead-acid batteries. AGM batteries have a higher price due to their lack of maintenance when compared to flooded batteries, which offsets the risk of the batteries being destroyed due to their flooded counterpart’s lack of maintenance. One of the disadvantages of an AGM battery is that once it has been overused, there isn’t much that can be done to repair the damage. AGM and flooded batteries are less expensive than lithium batteries up front, but their lifespans are far shorter.
How many solar panels are required to power an off-grid home?
Let’s pretend we have some 300 watt solar panels and you’re looking for a way to power your home. Because you don’t have access to the grid, off-grid solar is your best alternative for meeting your energy needs.
Assume that each panel on your rooftop receives about 8 hours of sunlight per day. A 300 watt panel exposed to the sun for 8 hours each day will create around 2.5 kilowatt-hours per day. We can acquire a solar output of roughly 900 kilowatt-hours per year if we multiply this by 365 days per year. In a nutshell, each solar panel will generate 900 kilowatt-hours each year.
How much electricity does your house consume? According to most estimates, a typical American home (2,000 square feet) uses about 11,000 kilowatt-hours each year. When we divide our entire consumption by the estimated production of one solar panel, we discover that around thirteen solar panels of this size would be sufficient to power a home of this size. Your energy consumption will be substantially lower if you have a smaller home or are running an RV, and you’ll need fewer panels.
To go off-grid, how much solar and battery do I need?
Given that the average solar battery has a capacity of around 10 kilowatt-hours (kWh),
- You’ll need enough battery storage to cover your energy demand when your solar panels aren’t producing (about 2-3 batteries) if you want to save the maximum money possible.
- When the grid goes down, you usually just need one solar battery to keep the lights on.
- If you want to be entirely off the grid, you’ll need a lot more storage capacity, like 8-12 batteries.
You’ve probably heard of the term “getting off the grid.” But what exactly does it imply? Going off the grid entails completely cutting off your power source from your utility company. A widespread myth is that all you need to do is purchase solar panels. Solar panels, in fact, make you more linked and dependent on the grid than ever before if you don’t have a home solar battery. In fact, without a solar battery, your solar panels will turn off if your grid loses power.
This article discusses how to actually go off the grid with a home solar battery, and how to do so in a way that saves you money while also offering you more independence and even protection against blackouts and power outages.
Solar panels convert sunlight into electricity. It’s fantastic. Solar panels require little maintenance after installation and typically survive for more than 25 years. That’s a quarter-century of free, clean energy.
Solar panels create electricity only when the sun is shining. Solar energy will be used by any appliances, lights, or plugs that utilize electricity throughout the day. However, because most individuals aren’t at home during the day, most of the electricity generated by solar panels is returned to the grid. In some situations, your utility will compensate you for the excess energy you use, but solar panels, like your home appliances, are reliant on the utility system. When the grid goes down, your solar panels fall down with it.
Grid failure causes solar failure for grid-tied solar panels, therefore solar panels alone won’t get you off the grid. Even if they could work while the grid was down, you’d still be in trouble because solar panels only generate electricity during the day, leaving you in the dark all night. This isn’t ideal.
Off-grid living takes more than simply solar panels. Going off the grid necessitates a technique to store and manage electricity usage so that you can have power at night or on overcast days. In a nutshell, moving off the grid necessitates the purchase of a home solar battery.
You can create all of the electricity you need with solar panels and then store additional electricity in your solar battery for times when your solar panels aren’t generating any. A solar battery for the home functions similarly to a power reservoir. Water reservoirs deliver water on a continual basis, overcoming the erratic nature of natural water flows. In an off-grid residence, home batteries provide constant electricity, countering the erratic nature of natural solar fluxes.
Now that we know what it takes to go off the grid, the issue is: should I go off the grid? The majority of the time, the answer is no.
In most states, installing solar panels is a no-brainer. They help you save money, lessen your environmental effect, and don’t demand any attention or work on your part. There is a solar system that is the right size for any home. Experts such as Swell can examine your energy usage and roof space and develop a system that will save you money on electricity.
However, going off the grid and ensuring you have enough energy requires a far larger solar system than is best for cost savings. You’ll have to spend substantially more money on a solar installation if you need to generate enough electricity to last you through the night and a string of overcast days. While Swell can finance most installations with no money down, these larger systems may cost you more than they save you.
You’ll also need a huge solar house battery that can store enough energy to carry you through the night and lengthy periods of overcast days, in addition to a larger and more expensive solar system.
So, should I get completely off the grid?
Despite the initial cost, many people should consider moving off the grid.
Do any of the following remarks strike a chord with you?
What solar-related equipment is required?
- Solar panels, inverters, racking equipment, and performance monitoring devices are all required to go solar.
- You may also wish to consider an energy storage system (sometimes known as a solar battery), especially if you don’t have access to net metering.
- In most cases, equipment contributes for only around 25% of the overall cost of your solar system; soft costs make up the majority of the total cost.
What is the finest source of off-grid power?
The best off-grid power sources are listed below.
- Propane. This is our enormous propane tank, which powers our off-grid boat access cabin at the moment.
- System of Solar Panels What exactly is this?
- A micro-hydro turbine is a small hydroelectric generator.
- The wind (Micro Wind Turbines)
- Geothermal Energy on a Small Scale (Mini-geo)