How To Hook Up A Solar System

Designing and installing a solar array for personal use can be a daunting but rewarding challenge ...... If you know what you're doing. Learn all the pros and cons, as well as the ins and outs of solar DIY here.

It's never been easier to fully power your house, vehicle, cabin, or boat in the sun in 2020. For starters, the International Energy Agency recently stated in its 2020 Outlook report that solar power - the "new king" of electricity - is the cheapest form of electricity ever. As a result, it's now almost certain that your utility bills will be significantly reduced or even eliminated through DIYSolar.

Even better, the cost of the materials needed for home solar power has fallen by 70% in the last decade. The biggest reason for the price drop is the photovoltaic (PV) panels themselves: a 90% drop in price (seen in 2019) from $2/watt to a paltry $0.20/watt!

On average, between 2010 and 2020 in the U.S., the installed cost of a residential solar system went from falling $7.50/watt to $2.50/watt. (The value varies from location to location, and the difference is a dollar or two whether you are using DC or AC power.)

This means lower upfront costs for you and a shorter payback period. In just 5 to 10 years - if you do everything right - it makes sense to believe that your DIY solar system will start making you money. That's good for you and good for the planet.

Where do you begin your do-it-yourself solar journey? Here you will find all the aspects of a home solar project you must research before implementing and operating. Following the step-by-step process outlined here ensures that you cover all the bases and make informed decisions and choices along the way.

DIY Solar Overview
Most homeowners who want to install solar will eventually find an installation company, but that's not the only option.

Do-it-yourselfers with a strong background or experience in electrical contracting will be able to complete a DIY solar project from start to finish after careful research and planning using the guide here.

If this sounds like you, then go for it! You're owning and operating a clean energy facility that will allow you to achieve energy self-sufficiency and a low carbon footprint for decades to come.

However, if you're a DIYer with little familiarity with setting up complex, multi-part electrical systems, then a DIY solar project done with professional help at several key points during the project (such as installation and wiring) may be the more prudent option.

If you have experienced people on your team, you'll avoid purchasing the wrong components or inferior materials. More importantly, you'll eliminate the possibility of potentially fatal accidents surrounding high voltage. You're also less likely to void any warranties.

The Main Types of Solar Power Systems
There are three types of solar power systems you can choose from to power your home and property:

Grid-tied - When energy demand is higher than system output, your solar array is connected directly to the utility. Any excess is sent to the grid. In most places, the electric utility is credited to your bill.

Grid Tie with Battery Backup (Hybrid) - This alternative allows you to store excess electricity generated by your home's solar panels in a backup battery. If your battery is fully charged, the excess power is sent to the grid, and in most cases you get paid for it. To meet your home's needs, the battery bank will activate and go off before peak power demand times take over.

Off-Grid - In this solar setup, you are completely independent of the utility supply. You own whatever your solar array output is. You can connect a backup battery to avoid power outages.

During the research and planning phase of your DIY solar project, you must ask yourself:

What exactly is the electrical demand and do I want to see my solar installation?

Is a grid-tied, off-grid, or hybrid setup best?

What are the necessary permits, licenses, and inspections I must obtain?

What are the best materials commercially available for my project?

How do I monitor my system to ensure it is always operating at peak efficiency and functionality?

What must I do to maintain my solar array so that it operates optimally throughout its lifecycle?

What solar equipment and materials do you need?

In the rapidly expanding renewable energy supply market, you must have multiple options for each component that must be integrated for your DIY solar system to work efficiently throughout its lifespan. Below is a list of the major components of most solar systems. (Note: Depending on your unique situation, you may need additional elements not listed here.)

Solar panels

Inverter

Power Optimizer

Charge Controller

Photovoltaic switches

Cables

Mounting racks or risers + brackets

Wiring and other electrical components

Batteries

After all the head work and logistics are done, you'll move on: mount the PV panels on a rack or pole somewhere on your property and connect them to your home electrical panel. Depending on whether you choose a grid-tied system, an off-grid system or a hybrid system, further electrical connections may be required to get everything up and running.

The Benefits of DIY Solar
Since purchasing a solar array is a major investment, it is important that you thoroughly research your options and weigh the pros and cons.

Here are the main advantages of DIY solar projects:

The cheapest way to electrify your home or vehicle.

The satisfaction of knowing you did it yourself.

For smaller electrification projects like outdoor lighting or tool sheds, it may be more cost-effective than connecting them to the utility grid.

Make a personal contribution to the renewable energy transition essential to curbing the climate crisis.

Disadvantages of DIY Solar

A do-it-yourself solar project comes with several drawbacks.

Here are the main drawbacks of DIY solar projects:

Building your solar array from scratch requires advanced technical knowledge and expertise that you may not have.

DIY solar home kits are typically designed to work off-grid for small projects. Today, solar kits that allow you to connect directly to the public grid are available and allow you to power your entire home.

Since the cost of complete solar installations has dropped dramatically in recent years, it is no longer cost-effective to perform the labor yourself as opposed to using a certified technician from an accredited company.

If your project is rooftop solar, you may accidentally damage your roof when drilling or improperly waterproofing it.

The damage you cause to your roof may void the warranty. Insurance may not cover any water or mold damage caused by leaks.

Working near high voltage can easily lead to accidental electrocution and possible death if you are not licensed.

If you are installing photovoltaic panels on your roof, the risk of injury or death from a fall may be too great to bear for someone who is not experienced in working at heights.

Installing solar energy yourself may prevent you from benefiting from certain local or state rebates or incentives that are available to you if you hire an authorized solar company.

After considering all the pros and cons of DIY solar, you may still be in favor of your project. If so, there is a long list of things to do before you get started. If followed carefully, you can still come out ahead.

Calculate your electricity needs
How much electricity do you want to generate with your solar panels? Answering this question is the most important aspect of your DIY solar project.

It will allow you to calculate how many solar panels you will need and, if needed, determine the size of the battery bank to be used for solar storage. Your energy usage will also determine the inverters and charge controllers you will need as well as the thickness of the wiring and the size of the fuses.

Every appliance must be included in this calculation to get the total power output. You will need the sum of all the power requirements of all appliances (e.g., refrigerator, oven, water heater, computer, TV, washer, dryer, hair dryer, clock, lighting, electric skirting boards, space heaters, cell phones), tablets, and so on.

Start by looking for the power consumption rating labels on all appliances and devices.

Some of these may show the wattage. In other cases, you will have to calculate it based on the given amperage or voltage. Use this formula for conversion:

Watts (W) = Volts (V) * Amps (A)

There are many online calculators you can use to add up. Or, you can set up a table like this:

NOTE: To fill in the fourth column, multiply the power output (column 2) by the number of hours of use per day (column 3). Then add up all the values in the fourth column to get the total number of watts you use per day, expressed in kilowatt-hours (kWh).

For all types of DIY solar projects, use the number of kilowatt hours (kWh) you used to make multiple calculations to calculate the number of solar panels and voltage needed to fully power your project. Free online calculators can simplify it and many other calculations associated with your DIY solar project.

DIY Grid Tied Solar
In a grid-tied solar setup, you are connected directly to the public power company's grid. This means that when your solar array produces more power than you need, it goes into the grid and is available for others to consume.

In most cases, your utility pays you for this energy through a process called net metering. This means that excess renewable energy is transferred back to your meter as it enters the grid, reducing your overall energy use (what you pay for).

Whether your electricity provider reimburses you at retail or wholesale depends on where you live. Unfortunately, not all states allow net metering.

To learn more about your state's net metering rules, visit DSIRE (Database of State Renewable Energy and Efficiency Incentives).

In a grid-tied system, when your energy needs are higher than the solar array can provide at night, for example, or when your panels are covered in the grid, it delivers the power you need to your home, avoiding interruptions.

Configurations required for a grid-tied solar system
In a grid-tied system, sometimes referred to as a grid-tied solar rooftop setup, several basic components are required for proper operation.

Photovoltaic panels

Mounting hardware

Pure sine wave inverter for grid-tied setups (converts DC from PV to household AC; pumps additional AC back to the utility grid)

DC or power optimizer (maximizes energy recovered from solar cells)

Grid disconnect (shuts down your system during a power outage)

DC circuit breaker (shuts down the array for maintenance)

Combiner box (organizes all components in one place)

Note: Three different types of inverters will work in a grid-tied system. Whatever you choose, make sure it is a pure sine wave type inverter. (For more information on this, see the Off-Grid section below).

String Inverters
String inverters are the most economical if your home is south-facing and shading is not an issue. With this inverter, current from a string of multiple panels is connected and fed into the inverter. If one panel in the string is affected by shading or fails, the energy output of the entire string is reduced.

String Inverter with DC Optimizer Technology

String inverters with DC optimizer technology overcome this problem. A separate power optimizer is connected to each solar module in the array and operates independently of all other modules. All DC from the optimizer is directed to the inverter where the DC-AC conversion occurs.

With this type of inverter, shadows or faults only affect specific panels (not the entire string). The operation of each panel can be monitored using this type of inverter.

Microinverters
A microinverter is an inverter that is mounted on each panel. The conversion of DC to AC occurs there. The AC power is then pooled together from your roof and fed directly into your home AC breaker box.

This type of inverter is the easiest to install. It also allows you to expand your solar array with other types or models of PV panels, each with its microinverter. (In contrast, to expand your solar array with a string inverter, you must use the same type of panels.)

When you consider all factors, a grid-tied system is the simplest and least expensive setup. Off-grid and hybrid systems require - in addition to the basic components of a grid-tied system listed above - a charge controller, battery bank, and other additional overcurrent protectors.

DIY Off-Grid Solar System
If you're interested in living off-grid in any way, or if you're far from a utility, DIY off-grid - sometimes called standalone - solar arrays are a no-brainer. Good news for 2020: whether you're energizing a remote cabin, van, RV, or boat, the possibilities for off-grid solar are practically endless.

Required Configurations for Off-Grid Solar Systems
The basic components of an off-grid system are similar to a grid-tied setup, but with the addition of:

Charge controller (sends DC to your backup battery bank, but turns it off from time to time to prevent overcharging)

Battery pack (needed for power when there is no sunlight)

Inverter (modified or pure sine wave, depending on your power needs)

Balance of System (BoS) components (wires, fuses, breaker box, etc.)

Su-KamSolar The following short video describes the different uses of a pure sine wave inverter versus a modified sine wave inverter. You will not only see the differences in the graphical illustrations of the two; you will also hear the comparison.

Determining Electricity Requirements for Off-Grid Solar Systems

For any type of DIY solar project, you must determine your power needs, as mentioned earlier. With off-grid, you can calculate that value and figure out the number of batteries needed to store it. You must also take this into account if you wish to use power that lasts for days or weeks.

This gets complicated for batteries because they are rated for storage at or slightly above room temperature. This means that if you are in freezing conditions, your storage capacity is significantly reduced (50% or more). Therefore, when you are in a cold place or season, you may need to significantly increase the size of your battery pack for this reason alone.

Battery Voltage
The voltage of the battery pack - whether 12V, 24V, or 48V - is also important. It affects the thickness (and price) of the wires connecting them and the cables leading to the inverter.

To determine the voltage, consider how many watts it will take to power all your appliances. A 12V battery pack may be enough for a cell phone and a few 12V DC appliances. However, if you want to generate 2,000 watts or more, a 24V or 48V battery pack makes more sense.

Time in the Sun
Another important consideration is the number of hours of sunlight your panel will receive each day. This number does not equal the length of daylight and varies with the seasons.

It depends on the angle of the sun relative to the direction of the panel. A map of sun hours in the United States is available through the National Renewable Energy Laboratory (NREL).

Charge Controller
Once you know the solar array voltage and the battery bank voltage, you need a charge controller to manage both. There are two basic types of charge controller technology available: PWM (Pulse Width Modulation) or MPPT (Maximum Power Point Tracking).

When the voltages match, a PWM charge controller is sufficient. When the voltages are different, use an MPPT controller.

DC/AC Converter
Last but not least is the inverter, which you need to convert the DC power in the module to AC power for devices that run on AC. In addition, you need to know what type of AC power the inverter requires. In the U.S., it is 120/240V split phase, 60Hz.

While some inverters can be configured, others are fixed. Check the inverter specification sheet (in the manual or on the company's Web site) before you buy to make sure you have what you need for your system.

Further considerations
A further complicating factor is that some appliances use 240 V, while others use 120 V. Not all inverters produce 240 V, so you may need to stack (i.e., connect) two inverters rated for 120 V to meet all your power needs. Double-check the spec sheet to make sure you're using the right equipment.

One last thing: Inverters are designed to match a specific battery whether it's 12V, 24V, or 48V. so you'll need to determine the size of the battery bank you'll be using before you buy an inverter.

If you think you might want to build solar arrays and/or battery storage capacity in the future, buying inverters that can handle the extra voltage now will save you from having to make expensive inverter upgrades later.

DIY Hybrid Solar Systems
Combining the functionality of both grid-tied and off-grid solar systems, hybrid systems enjoy the best of both worlds. You can store solar energy for nighttime use or in the event of a power outage.

This is ideal for homeowners in certain areas who would otherwise have to pay higher peak rates for grid power in the evening or at night.

However, if you are in an area with good net metering and minimal outages, a standard grid-tie system may be your best option.

The diagram below illustrates how a hybrid system works:

A special type of hybrid inverter is used in this type of system as shown in the diagram. It is also important to note that if you choose this setup, the batteries should be purchased at the time of installation. Battery technology is evolving rapidly and waiting too long may result in incompatibility with your hybrid system. This could mean you'll need to make a lot of expensive upgrades later.

For hybrid systems, AC-coupled batteries are common. These batteries house both DC from the solar array and grid AC for alternating current (AC) . Currently, the Tesla Powerwall is one of the most popular choices for AC-coupled batteries.

In contrast, DC-coupled batteries store DC power from solar panels and convert AC power from the grid into DC power that is also stored in the battery.

PV systems using DC-coupled batteries are more energy efficient than current AC-coupled batteries. This difference is more noticeable in large-scale installations. Therefore, it may not affect the efficiency of your home solar installation.

Which type of solar panel is best for your DIY solar project?
Three main types of solar panels can be used for residential projects.

Monocrystalline solar modules consist of 60 or 72 solar cells that are made of uniformly black silicon with an outer glass and metal frame. Each cell has rounded white edges. Monocrystalline panels are slightly more expensive than other types of panels but are much more efficient. They convert up to 23% of sunlight into electricity.

Polycrystalline solar panels also contain 60 or 72 solar cells, each perfectly square in a mottled blue color. They convert about 15 to 17 percent of the solar energy into usable electricity. Polycrystalline panels are slightly cheaper than monocrystalline modules.

Thin-film solar cells are lightweight and flexible sheets of photovoltaic material that are applied to solid surfaces such as glass. Thin film is even less efficient than other types, typically only 10-13%. They are also cheaper.

Choosing the right solar panel for the job
If you have limited space for your DIY solar project, monocrystalline panels are the best choice because they have the highest efficiency and cost similar to their polycrystalline cousins.

If space isn't an issue and you're trying to keep costs down - even in small ways - polycrystalline panels may be appropriate.

Thin film is not suitable for small solar installation projects, nor is it worth it.

DIY Solar Frequently Asked Questions
For a project as complex and expensive as DIY solar, you need to get it right. Here are some questions you may have been wondering about and the answers.

1. are grid-tied, off-grid, or hybrid solar systems best for DIY solar projects?

There is no right answer to this question. It depends entirely on your goals, technical knowledge, electrical experience, energy needs, and your location.

For example, if your goal is to power an entire 2,000-square-foot home for a family of four and you have net metering with few outages, a grid-tied system is the most economical.

However, if you only want to energize a secluded hunting shelter in the fall, then an off-grid solar system is your best bet.

If you don't have access to net metering, your utility company charges high rates for peak usage, or you have frequent power outages or blackouts, a hybrid solar system is the best option.

2. What are the hidden costs of a DIY solar project?

Before your DIY solar project can be put into operation, you will have to pay several permitting and inspection fees from your local jurisdiction and power company. Talk to them to find out what you have to do and when. Even missing one could delay or even prevent your project from being completed.

But before you start doing research for your solar system, check to make sure that unlicensed homeowners can install a grid-tied solar array. If not, you will have to hire a licensed solar company. This could be thousands of dollars more than your initial budget.

Your home insurance may increase due to panels on your roof or property. Contact your agent before you begin to determine if an annual increase is within your budget.

If you're not completely sure if you've purchased all the right components, make sure they're returnable before you take them out of the box. If you are wrong and need to replace the materials, you will be disappointed with the extra cost if you are unable to get a refund for that item.

3. As an independent homeowner with a solar installation, am I eligible for any tax credits?

In the U.S., the federal solar tax credit, also known as the Investment Tax Credit (ITC), allows you to deduct 26% (decreasing to 22% in 2021) of the cost of your solar installation, with no cap. You can perform this as an installer or hire a company to do the work.

At this point,thereisnoplantoextendthistaxcreditpast2021tohomeownersunderthecurrentAdministration. althoughanewlyelectedexecutivebranchandCongresscoulddoso.

Solar Renewable Energy Certificates (SRECs) are another incentive for homeowners. Through this program, you can sell energy certificates to the utility and receive cash back. The system works like a stock exchange.SREC values vary by state and month.

You must check with your state and local authorities for any other incentives or rebates. These may depend on you hiring an approved solar company to perform the installation.

Summarizing DIY Solar
The most important parts of a DIY solar project are planning and design. For these steps, you will have to do a lot of research.

A key number needed for all calculations is the watt-hour power you want the solar array to provide for all the equipment consumed in a day. If you are including battery storage, it is also important to know how many days of power you want to reserve.

After figuring this out, the next step is to purchase the necessary components for your grid-tied, off-grid, or hybrid system. After obtaining all the necessary permits and receiving an inspection, you can install the panels. Before they go online and start generating electricity, they must be inspected one or two more times.

When done correctly, your DIY solar project can provide you with decades of clean energy. It's a win-win for both you and the planet.