How to choose a solar kit

How to choose a solar kit

With so many options, you may be unsure of how to choose a solar kit that is right for your project. This article provides a quick guide with practical tips.

There are three primary drivers of a solar kit and its price:
1) the solar panel
2) the solar inverter
3) the options.

What to know about solar panels

To keep things simple, there are THREE basic types of solar panel: XL-size, standard-size, and premium.

XL-size solar panels are the most powerful because they have physically larger dimensions, generally more than 80 inches by 40 inches. That adds about one or two feet to the size. XL-panels usually offer the best value in terms of price and performance. These panels are considered commercial-grade, designed for larger roofs and ground mounts. They typically provide more power and are a better value with a lower price. They have similar manufacture, testing and warranty as other panels. If you have the space to fit XL-panels, they usually offer the best deal.

Standard-size panels are generally more than 65 inches by 40 inches. These are considered residential, rooftop panels. They often have black frames and can come with a white or dark backsheet for that sleek, all-black appearance. For a smaller roof, the standard-size could be the best fit.

Premium panels are generally standard-sized, but they can vary a few inches in height or width. Premium simply means they are more efficient because they generate more power per square inch. However, the premium panels can cost 30% to 50% more for the greater efficiency. If the roof space is limited, then a premium panel may be the way to go.

Keep in mind that your fridge does not care about the solar panel. They all make the same electricity. They all have similar manufacture, testing and warranty. They all have the similar UL test certification. They all qualify for same incentives and tax credits. They all have a long lifespan to work for a long time.

On any given day, SunWatts has around 60 different models of solar panel in stock. We can build a solar kit to meet your needs.

What to know about solar inverters

There are FOUR basic types of solar inverter: String, String + Optimizer, Micro-inverter, and Hybrid.

A grid-tied, string inverter is the most economical approach. Works just fine in direct Sun when shade is not an issue. Multiple strings, or groups of panels, are wired together, and then connected to the inverter. Each string operates independently. The string inverter may need replacement in 15 to 20 years. Ideal for ground-mounted systems or buildings where rooftop shutdown is not required.

A string inverter with Optimizers has a small device added to the back of each panel to "optimize" performance. Each panel operates independently, it can be monitored, and includes rooftop shutdown capability. Optimizers help minimize shade losses and improve overall performance.

Micro-inverters are also a device added to the back of each panel to "optimize" performance AND convert from DC to AC power. Each panel operates and can be monitored independently, with rooftop shutdown capability. Micro-inverters help minimize shade losses and improve overall performance. The smaller electronics have a longer lifespan, and a brand like Enphase has a 25 year warranty. The latest Enphase IQ8 microinverters are also hybrid, so they combine the best of all features.

Finally, a Hybrid inverter can work both on-grid, or off-grid with optional batteries. The solar panels and storage batteries are connected in one unit. The hybrid inverter also has an internal power transfer switch to deliver essential power during an outage. An external switch many be needed for whole-house power. Some hybrid inverters even let you connect a fuel generator as another power source to charge your batteries and power your home or business.

You can add rooftop shutdown or optimizers as needed. Some customers buy a hybrid inverter to be battery-ready, and future-proof the system in anticipation that battery prices will decrease over time. 


What options do I need for my solar kit?

There may be several options available for your solar kit: Rooftop Shutdown, Ground Mounting, Battery Storage and Installation.

Rooftop shutdown is an option for string inverters that provides compliance with safety Code in certain jurisdictions. Shuts power down within 1ft of panels on a rooftop. This is not required for a ground mount or buildings like a barn or detached garage. Varies by local building department Code requirements.

The solar kits include rooftop mount for shingle, tile or most metal roofs. You can choose the ground mounting option to add hardware and the 2 inch Schedule 40 galvanized steel tubing for a foundation that can be placed almost anywhere.

Battery Storage gives you the ability to have power during a black-out or grid outage. You can also use the battery daily for a specified time window of your choosing. To determine your battery size, you want to know how many kWh are consumed for an average day.

Kits are set up for DIY or your hired labor, with no experience necessary. You can add full service installation to see the SunWatts price. This option is available on a select project basis, and not available is certain geographic locations.

The value of good design

Most of the solar kits include an up-front design in the price. We want to make sure you get the right kit, with the right parts, for your project. The design covers topics like the power consumption, system sizing, the electrical connection and the structural mounting. Once the design is complete and the order placed, we will prepare a custom permit plan blueprint for the project. You can provide the plan to the local building authority and utility for net metering approval. This value-added service is unique to SunWatts. The solar design can be ordered separately to get the project started. Then you will get credit for the design fee with solar kits that are 5kW size or larger.

How to Get Started

Now that you understand how to choose the right a solar kit, follow this link to START A SOLAR DESIGN.

Choose a Solar Kit