Self build solar panels. Video: Why We Need an Inverter in a Solar PV System

# Self build solar panels. Video: Why We Need an Inverter in a Solar PV System

## Steps to Build a DIY Off-Grid Solar PV System

Day by day the price of solar panels falls gradually. But still, installation of a complete off grid solar system is costly. That’s why I decided to write this guide on how to get all the components of your solar system separately and assemble it all by yourself.

If you have decided to install a solar panel system to cover your home power needs, then this tutorial is for you.

I have tried my best to guide you step by step, from buying different components to wiring everything by yourself.

You have to know some basic electrical and math for designing the entire system. I have also attached links of my other instructions to make the charge controller and energy meter.

For an off grid solar system you need four basic components

Here’s how all the pieces fit together:

How the solar system fits together

Besides the above components you need a few more things like Copper Wire, MC4 Connector, breaker, meter and fuses, etc.

In the next few steps I will explain in details how you can choose the above components according to your requirement.

Note: In the pictures I have shown a big solar panel of 255W @ 24V, two batteries of 12V @ 100Ah each, 30A @ 12/24V PWM solar charge controller and a 1600 VA pure sine wave inverter. But during the calculation I have taken a smaller solar system example for better understanding.

Before choosing the components you have to calculate your power load, how much time it will run, etc. It is very simple to calculate if you know basic math.

• Decide what appliances (light,fan,TV etc ) you want to run and how much time (hours).
• See the specification chart in your appliances for power rating.
• Calculate the Watt Hour which is equal to the product of the power rating of your appliances and run time (hours).Load Calculation Example:Lets you want to run a 11W compact fluorescent lamp (CFL) for 5 hours from a solar panel, then the watt hour is equal to: Watt Hour = 11W x 5 hr = 55
• Calculate the total Watt Hour: Just as with the CFL we’ll now calculate the watt hour for all the appliances and add them together.Example:CFL = 11W x 5 hr = 55Fan = 50 W x 3hr = 150TV = 80W x 2hr = 160 Total Watt Hours = 55150160 = 365

Now the load calculation is over, next thing is to choose the right components to match your load requirement.

If you are not interested in doing the above maths then use a load calculator for this calculation. There are many such load calculators available in the internet, for example this Off Grid Load Calculator.

## Step 2: Battery Selection

The batteries I use for my solar system

Top view of the batteries

The output from the solar panel is dc power. This power is generated during day time only. So if you want to run a dc load during day time then it seems to be very easy. But doing this is not a good decision because…

• Most of the appliances need a constant rated voltage to run efficiently. Solar panel voltage is not constant, it varies according to the sun light.
• If you want to run the appliances during the night then it is impossible.

The above problem is solved by using a battery to store the solar power during the day and use it according to your choice. It will provide constant source of stable, reliable power.

There are various kind of batteries. Car and bike batteries are designed for supplying short bursts of high current and then be recharged and are not designed for a deep discharge. But the solar battery is a deep-cycle lead-acid battery that allows for partial discharge and allows for deep slow discharge. Lead acid tubular batteries are perfect for a solar system.

Ni-MH batteries and Li-Ion batteries are also used many small power application.

Note: Before going to choose the components decide your system voltage, 12/24 V or 48 V. The higher the voltage, the lesser the current and the lesser the copper loss will be in the conductor. This will also reduce your conductor size. Most of the small home solar systems will have 12 V or 24 V.

In this project I’ve selected the 12 V system.

### Rating of Battery:

Batteries capacity are rated in term of Ampere Hour.

Watt Hour = Voltage (Volts) x Current (Amperes) x Time (Hours)

Battery Voltage = 12V ( as our system is 12V)

Battery capacity = Load / Voltage = 365/12 = 30.42 Ah

But batteries are not 100% efficient, assuming 80% efficiency

Capacity = 30.42/0.8 = 38.02 Ah

By taking some margin you can select a 40Ah deep cycle lead acid battery.

## Step 3: Solar Panel Selection

A big 255W solar panel @ 24V

Solar panel ratings for the 255W solar panel

The Solar Panel converts the sunlight into electricity as direct current (DC). These panels are typically categorized as mono crystalline or poly crystalline. Mono crystalline are costlier and more efficient than poly crystalline panels.

Solar panels are generally rated under standard test conditions (STC): irradiance of 1,000 W/m², solar spectrum of AM 1.5 and module temperature at 25°C.

### Rating of Solar Panel:

The solar panel size should be selected in such way that it will charge the battery fully in one sunny day.

During the 12hr day time the sunlight is not uniform, and it also differ according to your location on the globe. So we can assume 4 hours of effective sunlight which will generate the rated power.

So total power output of Panels = 12V x 40Ah = 480Wh

Power to be generated per hour = 480 / 4 = 120W

By taking some margin you can choose a 125 W, 12v solar panel.

## Can you install solar panels yourself?

The cost of designing, buying, and installing solar for the average household in the UK is around £6000. Of that £6000, approximately 10% goes to the cost of hiring a pro-installer. In other words, hiring a professional installer costs at least £600, which is concerning if you’re on a budget.

As a result, you end up wondering if you can install solar panels yourself.

And the answer is YES. You can DIY (do-it-yourself) install your own solar panels.All you need to do is invest your time, energy, and a little bit of elbow grease.

This lowers your cost of going solar by approximately 10% or more. For most homeowners, this is a worthwhile incentive to invest their time and efforts.

However, before going the DIY solar panels’ route, here’s what you need to know:

If you’re not as agile or handy as you used to be, we highly recommend hiring an installer, as rooftop solar installations can be dangerous if you are not careful. No amount of money saved is worth risking your well-being.

For large solar installations, it’s highly recommended to hire a professional installer.

In areas with strict PV regulations, a professional installer can help you process permits and other necessary paperwork. Some utilities need a certified electrician’s signature as proof your system can be connected to the grid safely. Besides, when you apply for a Smart Export Guarantee (SEG) from your energy provider, they might need an MCS certification and a DNO (district network operator) approval.

## How much does it cost to install solar panels?

The cost of installing solar panels will vary depending on:

The installer you choose

On average, the cost of hiring a professional installer can range anywhere from £600 to a few thousand pounds. According to the EnergySage Solar Marketplace, the average cost of labour when installing a solar system is approximately 10% of the cost of all your components. If you wanner know how much solar panels are in the UK. click the link.

So if your components cost around £6000, then the cost of installation will be around £600. Please note that this figure is an estimate and may vary, so it’s best to cross-check with an installer near you.

## DIY solar panel installation process

There are a few stages you need to take care of before you start your DIY solar panel installation process.

One of the stages is quite obvious, which is buying the equipment you want to install. However, other lesser-known but important stages are:

Energy Usage Calculation (load or amount of electricity you use each day)

Solar Panel System Sizing

## How to install a DIY solar panel system at home?

The installation process for a DIY solar panel system can be broken down into 6 basic steps:

Step 1: Calculate Your Daily Energy Usage

If you’re connected to the grid, and want to find out how much you use daily, you need to look at your utility bills. On your utility bill, you will find the amount of Wh (Watt-hours) or kWh (kiloWatt-hours) used that month. For even better results, use the bills for the last 3 months to work out an average monthly usage. Once you have your monthly usage, divide that figure by the number of days in a month to find your daily usage.

Alternatively, you can sum up each of your device’s wattage and the number of hours used to find out the total energy you use daily.Our online solar panel calculator can help you here.

You need to decide if you are going to substitute all or part of your daily energy usage with solar power. You can choose to build a completely offgrid solar system that will power all your devices without any help from the grid.

Or, you can choose to build an on-grid solar system, also known as a grid-tied system, that only substitutes a fraction of your daily usage with solar power.

If you are building an off-grid system, you definitely need a solar lithium battery. On the other hand, an ongrid system can do without a battery bank due to the Smart Export Guarantee (SEG). The only drawback of an on-grid solar installation without solar battery storage is that you won’t have any backup power during emergencies.

Step 3: Size Your Solar Panels

Once you know how much power you want to generate with solar, you can calculate how many solar panels you need to produce that much power. We will explain how to size your solar panels later in this article.

Step 4: Purchase Quality Solar Components

After determining your daily usage and optimal panel output, you can start buying all the parts you will need for your installation, including:

Step 5: Install Your Railings, Mounts, and Components.

Once you’ve gathered all your components, you can start preparing the areas where you will install your components. This usually involves:

Mounting the railing for your panels on the roof

Creating or clearing a suitable space for your inverter and battery bank,

After preparing the installation zones, install the components. This involves:

Lifting solar panels onto the roof and bolting them to the railings;

Screwing your inverter onto the wall;

Finding a safe space for your batteries. The area shouldn’t be exposed to direct sunlight nor extreme temperatures (hot/cold);

Installing the joining cables and connectors.

Once you know which circuits you want to power with solar power, you can choose to join or replace the wires with the power supply of your choice. For example, you can choose to power only your lights and a few sockets, or you can choose to power all your circuits.

## How To Design a Solar Power System

Designing a solar power system means determining the size of the system you need. This size mainly depends on the total electricity requirement of all the appliances the system will power.

To do this, list all your appliances and their power (hourly) and energy (daily) consumption. The power rating of each appliance is given in watts (W), and often noted on the appliance. You can also use online tools to find out the power consumption of your appliances.

Calculate the energy consumption by multiplying power consumption by hours of use. Once you know the power rating of all appliances you plan to run on solar, make a table with power and energy values.

Here’s a sample table. Note that values in the last column are products of the preceding two columns (watts and hours).

The above table indicates that at any point in the day, the maximum power draw from the solar panels is 470 W, and that the total energy consumed in a 24-hour cycle is 2,740 Wh, or 2.74 kilowatt-hours (kWh). Let’s see how to use these numbers to calculate the size of solar panels, inverter, and battery. We begin with the battery.

### Sizing the Solar Panels

To size your solar panels, begin by finding out the average sunlight hours in your location. You can find the daily sunlight hours for any location from one of the many sources on the internet. Once you have that number, below is the simple calculation to find out solar panel size.

Total energy required (Wh) ÷ daily sunlight hours (h) = solar panel size (W)

Assuming that the location in the above example receives about 4.5 hours of sunlight daily, we have:

2,740 Wh ÷ 4.5 h = 608 W panels

Again, with some safety margin, we can use two 350-watt solar panels. These two panels will be connected in series as shown below.

### Sizing the Battery and Charge Controller

Most companies now offer batteries specified in Wh or kWh. For the load profile in our above example, the battery should be able to store a minimum of 2.74 kWh. Add some safety margin to this, and we can use a reliable battery size of 3 kWh.

Selecting a charge controller is similar. Look for a charge controller with a voltage rating that matches the panel and battery voltage (e.g., 12 V). Check the controller specs to ensure its current capacity is higher than the rated current of the solar panels (e.g., use a 20A controller for 11A solar panels).

### Choosing the Inverter

Your inverter selection depends on the ratings of your battery and solar panel. Choose an inverter with a power rating slightly higher than your panels. In the above example, we have 750 W panels and can use a 1,000 W inverter.

Next, make sure that the inverter’s PV input voltage matches the voltage of the solar panel (e.g., 36 V), and the battery input voltage matches the voltage rating of your battery (e.g., 12 V).

You can buy an inverter with integrated ports and connect your appliances directly to the inverter, for ease of use.

### Choosing the Right Cable Sizes

For small systems like the one we are designing, cable size is not a big concern. You can choose to use a general, 4 mm cable for all your connections.

For larger systems, correct cable sizes are essential to ensure safe and optimum performance. In that case, make sure to use an online cable size guide.

## Installing the System

By this point, you will have all the correctly sized equipment. This brings you to the final step — installation. Installing a solar power system is not complicated. Most modern equipment comes with ready-made ports and connectors so it’s easy to connect the components.

When connecting the components, follow the wiring diagram shown below. This will ensure that the power flows in the correct sequence and direction.

## Final Thoughts

Going solar does not mean you must hire a team and spend thousands. If you are installing a simple, small off-grid unit, you can do it yourself with a little math and some basic electrical knowledge.

Alternatively, you can also choose a portable solar system, which uses a device that combines the battery, inverter, and other electronics into a single unit. All you need to do is plug your solar panels into it. This option is slightly more expensive, but is also the simplest.

### By Aniket Bhor

Aniket Bhor has an M.S. in Renewable Energies and about a decade of experience working in the solar power industry — overseeing solar panel manufacturing and installations. He has written for renewable energy organizations worldwide, and is a climate enthusiast and avid cyclist.

## The Cost of Solar Energy

Are you asking yourself “how much for solar panels?”

When it comes to installing solar panels at home, there are a few things to consider. The first is the cost of the system itself. Solar panel systems can range from a few hundred dollars for a small DIY setup to tens of thousands of dollars for larger systems.

The size and complexity of the system will also determine the cost. It is important to do your research and find out what type of system you need for your home in order to get the most benefit from it.

With solar energy, the costs and pricing estimates vary by state and region. Regions with higher usage and more sunny days per year tend to have more robust incentive programs in place that may make solar energy more accessible. However, other areas of the U.S. may not have the same level of development for solar-powered solutions.

How much you can expect to pay for a solar panel system is dependent on the number of panels required to meet your energy needs, the type of solar panel you choose, and the incentives available in your region. However, according to Forbes, “Solar panels cost, on average, about 16,000, or between 3,500 to 35,000 depending on the type and model.” That’s quite a range!

When considering the cost of solar energy, you may want to consider looking into wholesale options, as this may be the most cost-effective route. A solar wholesaler like altE can offer competitive pricing on solar systems for homes and help with understanding how a solar panel works and what components are needed to create a complete system.

At altE Store, our smallest tiny house kits start at 5000,500 and our Grid-Tied 10kW Residential Home Solar System with Battery Backup is around 26,000. This of course doesn’t include the labor cost to install the system, or other costs like permits. But the sky is the limit and we can design a perfect system for nearly any budget. Browse our large selection of solar power kits, send a quote request for a custom kit or give us a call and we’ll help you design the prefect system.

When it comes to installing solar panels at home, there are a few things to consider. The first is the cost of the system itself. Solar panel systems can range from a few hundred dollars for a small DIY setup to tens of thousands of dollars for larger systems.

When it comes to installing solar panels at home, the size and complexity of the system will determine the cost. It is important to do your research and find out what type of system you need for your home in order to get the most benefit from it.

## The Process of Installing Solar Panels

Installing solar panels in your home is a great way to save money and reduce your carbon footprint. However, it is important to understand the process of installation before making any decisions.

First, you’ll need to decide which type of solar panel best suits your needs. There are several options available, from smaller than 100watt solar panels to larger than 300w solar panels, flexible solar panels, bifacial solar panels, and more. Each type has its own pro’s and con’s, so it’s important to consider which type will be most suitable for your home.

In general flexible solar panels are less efficient than traditional solar modules and don’t have very long warranties. Bifacial solar panels work best when you have a reflective surface behind them, like a white roof or light colored gravel. Most people go with traditional solar panels as they have the best price points and functionality in most circumstances.

Next, you’ll need to choose how much power you want to generate with your solar panels. You can either purchase a solar system for homes that comes with a certain number of panels and an inverter, or purchase each component separately and assemble your own system. In either case, it is important to know how much power you will need before buying anything.

Once you’ve purchased all of the necessary components, you’ll need to install them. Depending on where you live, you may be able to do the installation yourself or hire a professional. If you decide to do the installation yourself, make sure to read up on safety guidelines and double-check all connections before turning on your system.

If you plan on having a battery bank for your home solar power system, it’s essential to research the right type of batteries for home solar. The most common type is a 24V battery, although there are other options available depending on how much energy you want to store and how much you’re willing to spend.

By following these steps and researching the various components involved in a home solar power system, you can ensure that your system will be both safe and efficient. With the right preparation and planning, you’ll be able to enjoy the many benefits of a solar powered home for years to come!

## Do-It-Yourself Tips for Installing Solar Panels

Installing solar panels at home is a great way to save money on electricity and reduce your carbon footprint. You can also find many benefits from solar energy, such as independence from the grid and increased home value. But before you begin your solar project, it’s important to understand how much solar energy you need, the cost of solar energy, and the process of installing solar panels.

When installing solar panels at home, it’s best to start by doing some research to determine what type of system is right for your home. Solar powered systems come in a variety of sizes and shapes, ranging from micro systems with 100Watt solar panels or smaller to gigawatt plus utility scale power plants!

Once you’ve decided how much power you need, you’ll need to find out how much for solar panels and other equipment like a 12v or 24V battery, a home inverter, and batteries for your home solar system.

Once you’ve chosen the right equipment, it’s time to purchase the supplies and begin installation. You can purchase the equipment from a solar wholesaler, like altE, online or on the phone. Make sure to read up on how a solar panel works and the basics of wiring a home solar power system so that you know what to expect during installation.

Once all of the solar components are installed, it’s important to consider a battery bank for your home solar system. This will store any excess energy your home produces for later use. Choosing the right batteries for your home solar system is key; look for high quality batteries that are rated for long-term use and make sure to research their warranties before making your purchase.

Installing solar panels at home can seem intimidating, but with the right preparation and research, it doesn’t have to be. By following these do-it-yourself tips for installing solar panels, you’ll be well on your way to creating a successful and sustainable home solar system. And if you decide the DIY route is not for you, give us a call and we’ll work to find a solar pro in your area to help.

## Wrapping things up

Many people around the world are looking for ways to become more energy efficient. One of the best methods is to install solar panels at home. Installing solar panels at home can be a great way to reduce your energy costs, help the environment, and have the freedom to create your own energy source.

Whether you decide to purchase the panels from a solar panel wholesale supplier and install them yourself or get a solar installation professional to do the work, the end result is a reliable source of clean energy. Additionally, you can pair the panels with a battery bank to store excess energy. Getting a solar panel with battery bank makes for a combo so you always have power when you need it. With some research and preparation, anyone can make their house solar powered in no time.

Deciding to use solar power to power and convert your home to a solar house is a Smart choice and investing in solar panels is an excellent way to save money in the long run. Solar panels are an efficient, eco-friendly way to power your home, so consider giving them a try. With the right solar batteries for homes, you can start seeing the benefits of going solar almost immediately.

Using solar power for your home has many benefits. Solar energy is a renewable, clean source of energy that can help reduce your electricity bills and your carbon footprint. Solar panels are becoming increasingly affordable and easy to install, making them an attractive option for homeowners looking to save money and reduce their environmental impact.

Most people choose to go solar for the following reasons:

1) Lower electricity bills – Depending on the amount of electricity you use each month, installing a system can result in a significant reduction in your power bills as it will rely less on grid electricity.

2) Environmental friendly – Solar panels rely on clean renewable energy sources rather than polluting fossil fuels used by most power utilities. This makes installing a system one of the simplest ways to reduce your carbon footprint and have less impact on our environment.

3) Tax credits and incentives– Many nations offer tax credits or other financial incentives when you install a solar panel system in your home or business premises. These incentives help offset initial installation costs.

Once you have the necessary information, you can begin to plan your solar panel installation. Start by researching the types of panels available and their associated costs. You should also consider the size of your home and how much energy you will need to power it. This will help you determine how many panels you need and what type of system would be best for your needs.

Next, decide whether you want to install the solar panels yourself or hire a professional installer. If you choose to do it yourself, make sure that you understand all safety precautions and follow all instructions carefully. You may also want to consult with an electrician before beginning any work on the wiring or electrical components of your system.

Finally, once everything is in place, connect the solar panels to your home’s electrical system and start enjoying clean energy from the sun! With proper maintenance, your solar panel system should last for decades and provide a reliable source of renewable energy for years to come.