How to Build DIY Solar Generator? [Expert Guide]

The best time to switch to green energy is today. Given the rising global issues with climate change, it’s risky to keep relying on fossil fuels to sustain our lifestyles. And thankfully, we live in an era where solar energy is affordable like never before.

What a time to be alive.

Solar generators are power banks for individuals who require charging beyond cellphones and pocket WiFi. We know solar energy might still be a “futuristic” concept for some households out there, but truly, having accessible, usable energy on the go is something we all need—and it doesn’t have to break the bank. This article will give you the information you need to build your DIY solar generator. We will walk you through the following:

How to determine the size of a DIY solar generator for your situation;
What materials do you need; and
How to put them all together;

What is a Solar Generator?

Before you create a homemade solar generator, it is best that you understand what it means and how it works.

The best way to do this is by breaking the term down word by word.

So, what do we get? “Solar” and “Generator.”

Let’s start with the word “Generator.” In power systems engineering, generators are machines that convert one form of energy to electric energy. That’s why we have a variety of them, such as fossil fuel, natural gas, hydro, geothermal, and wind, to name a few.

On the other hand, the term solar means “about the sun.”

Putting those words together, we can deduce that a “Solar Generator” is a device that can take in solar power and convert it to electricity.

The Problem with Solar

However, more experienced readers right now might be thinking:

“That’s just the gist of it! There’s more to it than that, right?”

We agree with you 100%. As a green energy warrior, the more you go down the road of solar, the more you realize that it has many limitations as a sustainable technology.

For example, one of the early problems with solar electricity is that you must use it as you produce it.

If we are to magically wave our wand and eliminate all the fossil fuel generators now, where do we get our electricity at night or if a cloud goes over our solar panels?

The Solution: Storing Solar Energy and More

That problem was one of the fundamental hurdles solar developers had to solve at the onset of the clean energy era.

This led to the development of the modern energy storage system (ESS), which is essentially the enhanced version of car batteries.

Having energy storage systems combined with a solar panel allows its users to harvest solar energy, store it, and use it for emergencies, during nighttime, or in situations when the sun isn’t as available.

From what we shared, you should realize by now that solar developers and policymakers are building a sizeable chunk of the green energy movement around solar technology. One of the main reasons for this is that solar power harnesses energy from the sun, making it a truly sustainable source of energy compared to the other variants. Aside from ESS, many other technologies are used to create solar generators, such as inverters, battery management systems, etc.

Functions of A DIY Solar Generator

Based on what we discussed, we can discern that essential solar generator operation involves harvesting, storing, and converting solar energy to electricity.

In addition, modern solar generators have other functions, such as battery protection and portability.

With these features in mind, let’s begin the solar generator DIY process by creating a master plan.

Planning Your DIY Solar Generator

A well-planned DIY portable solar generator comes with many benefits. Starting your DIY process with planning creates order in your workflow. It also helps you reflect on your goals and needs. From a financial perspective, knowing exactly what you want from your solar generator will save you a lot of money.

For example, knowing the maximum electric power and energy, you need for your devices will help you avoid excessive spending on oversized batteries and inverters.

Table 1: Sample Price Comparison of Inverters by Size and Quality

Inverter Size	Pure Sine Wave (Good Power Quality)	Price (Pre-tax)
500 Watts	No	$45
750 Watts	No	$65
1000 Watts	No	$80
1000 Watts	Yes	$140
2000 Watts	No	$170
2000 Watts	Yes	$260
3000 Watts	No	$300

In general, there are four steps to build your own solar generator:
1. Estimating Energy and Power Needs;
2. Purchasing Gears and Components;
3. Match component ratings;
4. Assemble the components;

I will describe these steps in detail below.

Estimating Energy and Power Needs

Estimating your energy and power needs can be done through the following steps:

List down your devices
Determine the continuous power ratings of each appliance
Gauge how long you will use each device daily to assess your energy needs

1. Write Down All the Devices

The first step is straightforward: List all the devices you wish to run through a solar generator. We understand that you have many electronics you want to power, but recall that the higher your power needs, the more expensive your solar generator project will get.

Therefore, we recommend limiting your devices to essentials or particular activities, such as backup power for your work-from-home setup or meal preparation appliances in the RV.

Table 2: Sample List of Appliances for Your Home Workstation

Devices / Appliances

Laptop

Cellphone

Internet Modem

Monitors x 2

LED Lamp

Table 3: List of Appliances to Prepare Meals in an RV

Devices / Appliances

Electric Stove

Coffee Maker

Microwave

Toaster

Mini Fridge

2. Determine the Power Ratings of Your Devices

Next, we need to know how much power you will need if you will turn all your devices on together.

Electronic devices usually come with a label that shows their power ratings.

Table 4: WFH(Work from Home) Total Power Needs

Devices / Appliances	Power
Laptop	150 Watts
Cellphone	15 Watts
Internet Modem	300 Watts
Monitors x 2	60 Watts
LED Lamp	15 Watts
Total	540 Watts

Table 5: RV Total Power Needs

Devices / Appliances	Power
Electric Stove	1,500 Watts
Coffee Maker	600 Watts
Microwave	1,200 Watts
Toaster	500 Watts
Mini Fridge	110 Watts
Total	3,910 Watts

3. Assess Your Energy Needs

Table 6: WFH(Work from Home) Power and Energy Needs

Devices / Appliances	Power	Time Used	Energy
Laptop	150 Watts	4 hours	600 Watt-hours
Cellphone	15 Watts	16 hours	240 Watt-hours
Internet Modem	300 Watts	4 hours	1200 Watt-hours
Monitors x 2	60 Watts	4 hours	240 Watt-hours
LED Lamp	15 Watts	8 hours	120 Watt-hours
Total	540 Watts		2400 Watt-hours

Table 7: RV Power and Energy Needs

Devices / Appliances	Power	Time Used	Energy
Electric Stove	1,500 Watts	0.4 hour	600 Watt-hours
Coffee Maker	600 Watts	0.1 hour	60 Watt-hours
Microwave	1,200 Watts	0.1 hour	120 Watt-hours
Toaster	500 Watts	0.1 hour	50 Watt-hours
Mini Fridge	110 Watts	24 hours	2,640 Watt-hours
Total	3,910 Watts		3,470 Watt-hours

Note: Energy (Watt-hour) is Power (Watt) multiplied by time (hour)

Based on our sample planning process, you will need 3,910 Watts and 3,470 Watt-hours per day for your RV meal preparation setup. On the other hand, your work-from-home setup needs 540 Watts and 2400 Watt-hours daily.

We realize that the items and ratings in our sample tables will likely differ from your cases. Feel free to create your personalized table before proceeding to the next section.

Gears and Components for Your DIY Solar Generator

Visual aids are perfect for helping people get an overview of a topic. It will also help you create order and retain information throughout this article.

That being said, let’s examine the blueprint below. Based on the image, we can summarize the components we need for your DIY solar generator kit, such as:

Solar Panel (Portable if needed)– A device that converts solar energy to electric DC energy;
Solar Charge Controller (PWM or MPPT)– A device that charges and protects your battery by controlling the voltage, current, and power input from solar panels;
Battery (12V and Lithium-ion)– A device used to store solar energy;
Inverter– A device that converts DC power from either solar panels or batteries to AC power used by common household appliances;
Wires, Terminals, and Adapters– Parts of a solar energy system used to connect the four main components mentioned above;
Fuses– An optional (but highly recommended) protection device that disconnects your solar energy systems during dangerous situations
Enclosure– An item that makes your DIY solar powered generator easy to carry. After all, it would save you much stress if you have something that holds everything together (except the solar panel).

Figure: A DIY Solar Generator Blueprint. Image reproduced from Portable Solar Power.

Matching the Ratings of DIY Solar Generator Components

Now that you have an idea of the primary components of your own build solar generator, let’s ensure they are all compatible. Note that when we say “DIY,” it doesn’t mean building the components from scratch. Rather, it means being able to assemble the parts that are compatible with each other in accordance with your energy needs and budget.

For starters, you should determine if you wish to use a 12-volt or 24-volt system. For beginners, we recommend the former.

Ensuring all your solar parts are optimized is simply a matching type game: Make sure your inverter, charge controller, and batteries have higher voltage and current ratings than your solar panel.

Let’s take the following example.

Sample DIY Solar Generator Shopping List

Main Components

Item	Voltage	Current	Power/Energy
Portable Solar Panel	20V	10A	200W
Charge Controller	100V	20A	12V/260W, 24V /520W
Battery	12V - 14.5V	80A	1200Wh
Inverter	12V	-	1000W continuous/ 2000W peak surge on start-up

The buying process starts with solar panels in our sample component list above.

Now, using our sample work-from-home setup, a 12-volt system should suffice, beginning with our solar panel with a 20-Volt and 10-Ampere input.

Using the power formula, 20V multiplied by 10A equals 200W.

Let’s move on to our battery component.

Given that our battery only accepts 12V to 14.5V, the 20V input from the solar panel is too much.

This is where the solar charge controller comes in. The MPPT charge controller we selected takes in the 20V and 10A from the solar panel and regulates it to 12V while maintaining the 200W power injected into the battery. Pretty cool, right? MPPT does increase solar system efficiency compared to PWM.

From here, it is smooth sailing. Just attach a 12V inverter to your battery, and you already have the bare requirements to operate a solar generator. Given that our sample setup includes sensitive gadgets, we recommend using a Pure Sine Wave Inverter.

Connectors and Enclosure

Electrical wires and fuses are invaluable in linking the main components together while ensuring safety. We recommend using 30A fuses, a 4AWG wire for your battery-inverter connection, and 12 AWG for the rest.

Figure: MC4 adapter (left) and Fuse (right)

We recommend using a shockproof hard case to protect your sensitive equipment from impact for the enclosure.

Figure: An industry-grade hard case.

Putting Together Your DIY Solar Generator

After all the planning we have done, all that is left is to put these things together. If you are not confident with your assembling, drilling, and installation skills, there is no shame in hiring an expert handyman or electrician to do the work for you.

Install the battery and inverter in your case

Often, batteries are the most significant components of a solar generator DIY. Therefore, placing them first inside your enclosure is a good idea. Also consider the battery type, I suggest you use lithium batteries, not lead acid batteries. And you may use deep cycle batteries. If you buy a suitcase-like hard case, put the battery at the bottom, wheel-end side.

Lastly, hold the battery in place using industry-grade clamp-down straps. Next up is the inverter. Place it in a position that allows some space for you to insert the cables coming from the battery and the devices.

You can also cut a hole in your hard case to make the outlets and USB more accessible. However, you risk exposing your sockets to the elements, such as rain, snow, etc.

Install the solar charge controller

Lastly, install the solar charge controller inside the case and hold it down using the same clamp straps.

Recall that the solar charge controller connects the solar panel to the battery. Therefore, you should install MC4 adapters into your charge controller if they aren’t included in your purchase. These adapters will connect your solar panel to your charge controller.

MC4 Adapters going into the charge controller

Install the Wiring and the Fuse

Now that we have finished installing our three main components, it is time to wire them up, as illustrated in our blueprint/wire diagram above.

Remember that there should be active connections between the following:

Solar panel and charge controller
Battery and charge controller
Batter and inverter

Final Thoughts

There you have it! The basics of making a DIY Solar Generator. We understand that first-timers like you might have more questions as you make this complicated setup. Reach out to us if you have any concerns or clarifications, and we will gladly help you!

Buy Growatt Portable Solar Generator!