How Much Solar Amp Hours Do I Need Off Grid?

What are some of the factors to consider while selecting a battery bank?

Input voltage would be one of them. In most cases, the input voltage of the inverter will be the determining factor. Typically, this will be 12, 24, or 48 volts, with bigger off-grid installations typically using 24 or 48 volts. In general, higher voltage necessitates less amperage input.

The battery’s amp hour or kilowatt hour capacity is the second factor to consider. Obviously, the larger the battery, the greater its storage capacity. As a result, it will be determined by the size of your system. In a typical off-grid cottage application, a 24 or 48-volt battery bank with a capacity of 600 to 800 amp hours would be used. In bigger systems, they can reach 6,000 amp hours or more.

What kind of cells are you looking for? Two volts more? What are the cell sizes? In the case of lead acid batteries, bigger equals more capacity. So, once again, the size of the cells you require is determined by the amount of capacity you demand. Finally, there’s technology. There are three types of lead acid: flooded, AGM, and gel. AGM or absorbent glass mat and gel batteries are both maintenance free and require far less attention than flooded batteries, which must be checked on a regular basis. These batteries are typically more expensive to purchase than flooded lead acid batteries, but for some people, the time and money saved in maintenance justifies the original cost.

Lithium batteries are also available now, and some people are exploring using them for off-grid applications. They are the most expensive to buy, but they give more cycles and amp capacity during the battery’s lifetime.

Each battery type has advantages and disadvantages; the one you choose will be determined by the sort of application, the loads you’ll be running, and your budget.

How much solar energy will I require for my off-grid home?

The number of solar panels required to go off the grid is purely determined by the following variables:

To rely totally on its own energy output, the average off-grid home requires roughly 7 Kw (or 7000 Watts) of power.

Solar panels come in a variety of shapes, sizes, and designs. The amount of solar panels you’ll need to go off-grid is determined by two primary factors: your energy needs and the performance output of each panel.

  • Standard testing conditions (STC) are used to rate panel performance: 1,000 W/m2, AM 1.5 sun spectrum, and 25 C module temperature.

A 100-watt solar panel, for example, is 47 x 21,3 x 14 inches in size. The dimensions of a 200-watt solar panel are 64 x 26 x 14 inches (these are rough estimates).

The larger the framework, the more photovoltaic cells may be installed inside of it, resulting in increased performance.

If your energy needs were the same as the average (7 kW), and you used 200-watt solar panels, you’d need about 35 panels to go off the grid. Alternatively, 20 350-watt solar panels might suffice.

You’ll need to calculate the total square footage to get an idea of how much space 35 solar panels will take up.

  • 35 solar panels will take up around 389 square feet of roof space on your property. This gives you plenty of room if you decide to add more panels to your system in the future.

To make things easier for you, we’ve put up this chart that shows you how many solar panels you’ll need based on your situation.

How do you figure out how much battery you’ll need for an off-grid solar system?

The next step is to determine the size of our battery bank! We’ll utilize the same scenario as previously, with a daily energy demand of 1.9 kWh in the winter. To calculate the total energy required for battery storage, multiply the number of days (of energy storage) by one minus the battery SOC we are ready to accept (bearing in mind that typical sizing calls for three days and a 50 percent SOC):

Daily energy use (kWh) x Number of days of autonomy / (1 SOC) = Battery bank size (kWh).

This figure, 11.4 kWh, is the entire quantity of energy that our battery bank must store when completely charged. Working using Amp-hours, a somewhat fictive quantity of Amps we can get out of the batteries for one hour before they are empty, is more convenient for batteries. The number of amp-hours (Ah) is proportional to the voltage of the battery bank. We’ll use a 24 volt battery bank in this example:

When single batteries are connected in series (positive to negative, etc. ), the Voltage of the battery bank is increased while the Amp-hours remain constant. Similarly, when two batteries are connected in parallel, the voltage remains constant while the amp-hours double. We may make this battery bank out of four Surrette S-550 batteries, each with a capacity of 6 Volt 428Ah. When you connect them in series, you have a total battery bank of 24 Volt 428 Ah, which is close enough for our needs!

In our example above, the complete off-grid system consisted of 5 solar panels rated at 295 watts each and 4 Surrette S-550 batteries. That’s pretty similar to our 4-panel cottage kit!

To live off the grid, how many batteries 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 roughly 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.

How many kilowatts does it need to power an off-grid home?

How to live off the grid in Australia on a shoestring budget! With so many alternatives for solar and battery storage, going off the grid with solar power has never been more affordable. As a result, many Australians are now considering completely unplugging from the electrical grid. For many people, ‘going off-grid’ and living off the grid has become a dream, and off-grid stand-alone solar systems have been shown to raise the value of a home while simultaneously lowering carbon emissions. You will no longer be reliant on mains power, which means that power outages will no longer be an issue for you and that high electricity costs will be a thing of the past. Doesn’t it sound ideal? Transferring your home from mains power to off-grid solar power, on the other hand, necessitates extensive planning. It’s not something you want to accomplish without first asking yourself a few key questions.

Do I want to go fully off grid with solar, or remain partly connected to mains power?

If you want to live fully off the grid, you’ll need a more powerful system than if you wish to stay connected. Most individuals will prefer to stay connected since they will always have a backup in case solar power storage is disrupted by prolonged bad weather. In this case, if solar electricity is insufficient to power your appliances, the grid will step in and provide the remaining energy. Your solar panels, for example, have generated 1 kW, but you’re using appliances that require 2 kW. The grid will then provide the remaining 1kW. Alternatively, if your solar panels generate more energy than you need, you can feed it back into the grid and get paid for’selling’ your energy to the utility.

You’ll need a system large enough to generate your power demands and charge your solar batteries if you wish to entirely detach from mains electricity. It may also be essential to have a large battery bank or a backup generator to store the solar electricity for later usage (for example, in the event of severe weather).

What Size Does My Off Grid Solar System Have To Be?

Examining your electricity bill is the simplest approach to determine the size of your solar installation. It should state the total number of kW your family consumed within the time period specified by the power company. You may calculate your daily kW usage by dividing the total kW by the number of days.

For example, your quarterly bill shows that you utilized 2000kW over the course of three months. The formula would be: 2000kW / 92 days = 21.7kWh average daily consumption.

If you want to live fully off the grid, you’ll need a system that can generate enough energy to fulfill your daily needs. Keep in mind that you won’t require 21.7kW of panels because they’ll provide power for several hours each day. In this case, 5-6kW of panels would be a good number. You might choose a smaller solar system for a hybrid system if you are still linked to the grid (e.g. 3kW and use the grid as a supplement).

Which Batteries Should I Use For Off Grid Solar?

You’ll need good solar batteries to store your solar energy. Smaller setups or shorter periods of time unplugged from the grid are suited for AGM/High Discharge deep cycle batteries. You’ll need large-capacity batteries that can store a lot of energy and survive for a long period if you want to live fully off the grid (e.g. 15 years versus 5 years for AGM). For these long-term systems, tubular gel batteries are excellent.

Are you interested in learning more about solar batteries? For additional details, see our previous blog post ‘How Do Solar Batteries Store Energy?’

Do you have enough space to install a Stand-Alone Solar System?

Solar panels are typically mounted on top of the roof of off-grid homes. It’s also vital to think about how many solar panels you can put up in the proper location to get the most sunshine without getting shaded by trees. This will almost certainly have an effect on the size of your solar system. On the other side, if you have a large enough piece of land that isn’t shaded, you can build your solar system there. You can even combine the two alternatives by installing some solar panels on your roof and the rest on your property.

Running Appliances for Off Grid Living – I want to run an air con with my solar system?

During the majority of the year, Australian weather can be extremely humid and hot. If you run your air conditioner virtually nonstop on hot summer days, you’ll need a solar system that can manage the load. It’s sometimes cheaper to spend a little more on a more efficient air conditioner than it is to acquire a larger battery bank or solar system to power an inefficient air conditioner.

How to get the Best Off Grid Solar System

Would you like to learn more about the best off-grid and stand-alone solar systems available in Australia? If you need experienced, personalised, no-obligation advice on Going Off The Grid With Solar and Battery Storage Power in Australia, email or phone our friendly experts on 1800 853 315, and your goal of living off the grid might be realized soon!

View our online selection of off-grid power solutions or contact one of our solar or battery experts now.

To go off-grid, how many solar panels and batteries do I need?

A fully off-grid system necessitates a large amount of space. Not only do you need space on your roof or lawn for +/- 20 panels (5kW system), but you also need space to house the batteries mentioned in point 4. The 20 to 30 batteries needed to run an off-grid system must be stored in a cool, dry location. The batteries’ lifespan is also influenced by the temperature in which they are stored.

You’ve probably heard the term “going off the grid,” but what exactly does that imply? Going off the grid entails completely disconnecting from your utility company’s electricity source. 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 are not 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 because you’ll 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?

How many amp-hours do I use on a daily basis?

We’re frequently asked how to figure out how many amp hours a customer needs to run a device or a series of devices.

As a result, we generated some notes on a variety of topics, such as “How to Calculate Battery Amp Hours” and other related topics.

So you have an appliance or gadget, such as a pump, and you’re trying to figure out what size battery you’ll need?

If the current drawn is x amps and the time spent is T hours, the capacity C in amp-hours is

2.88 amp hours C (amp hours) = 0.12 amps * 24 hours (keep going, not done calculating yet)

It’s not a good idea to discharge a battery completely throughout each charging cycle. For example, if you wish to utilize a lead acid battery for a long time, don’t charge it beyond 80% of its capacity, leaving 20% in the battery. This not only increases the number of cycles you get, but it also allows the battery to degrade by 20% before running time drops below what the design asks for.

When you deplete a battery quickly, some chemistries produce significantly fewer amp hours. The Peukart effect is the name for this phenomenon. In alkaline, carbon zinc, zinc-air, and lead acid batteries, this has a significant impact. For example, if you draw 1C from a lead acid battery, you’ll only obtain half the capacity you’d get if you drew at 0.05C. In NiCad, Lithium Ion, Lithium Polymer, and NiMH batteries, it has a minor influence.

For example, if you want your portable guitar amplifier to last an hour and it draws a steady 20 amps, you’d start with Step 1:

To run the amplifier for 1 hour at 20 amps average draw, you’ll need a 50 amp hour sealed lead acid battery.

Step 4: What if the load isn’t constant? The obvious course of action is the best course of action. Calculate the average power drawn. Consider a one-hour-per-cycle repeated cycle. It is made up of 20 amps for 1 second and 0.1 amps for the rest of the hour. The following is how the average current would be computed.

To put it another way, figure out how many amps are drawn on average then apply steps 1 and 2 to that result. In the case of tiny periods of high current, step 3 is extremely difficult to forecast. The good news is that a continuous 1C pull will significantly reduce capacity compared to short 1C pulses followed by a rest interval. So, even though you’re drawing it in high current pulses, if the average current drawn is around a 20 hour rate, you’ll get closer to the capacity indicated by a 20 hour rate. Actual test data is difficult to come by unless you do the test yourself.

Watts are the fundamental unit of power, while watt-hours are the amount of energy stored. The idea is to compute the amps at the battery voltage using the watts you know.

Let’s imagine you wish to use an inverter to power a 250 watt 110VAC light bulb for 5 hours.

Divide the watt hours by the voltage of the battery to get amp-hours of battery storage since watts = amps * volts.

By dividing the amp-hours by the battery voltage, the amp-hours will alter if you use a different voltage battery.

How many 200Ah batteries are required to run a home?

Number of batteries in total Divide the battery’s total energy (assuming you’re working with a 200Ah battery). It might be 150AH) if the battery voltage is multiplied by the capacity. That’ll be approximately two batteries. As a result, to power your load for 7 hours, you’ll need two 12V 200Ah batteries.