Which is for you? Grid Tied, Hybrid and Off Grid

Published January 15, 2016

We are frequently asked what happens when the grid is down and about batteries. Let’s review three types of solar systems; grid tied, battery backup and off grid. Which is for you?

This is by far the most common, requires the least maintenance, and is the least expensive. It also receives the TVA Green Power Providers solar buyback rate. However, grid tied systems are required to disconnect from the grid in the event of a power outage. This means you won’t have any power either. Whether this is an issue for you, depends on the individual. If you only lose power 2 or 3 times a year for an hour or 2, this shouldn’t be a problem.

On the other hand, if you live in an area with more frequent and sustained power outages, or live at the end of the distribution line (these are the last places to be restored), you may want to consider the other options.

Batteries provide backup power in grid outages, and depending on the system set-up, daily cycling. Solar plus battery systems are more expensive than grid tied solar systems because of the batteries, other necessary equipment and additional wiring. Backup systems are of 2 basic types, AC Coupled and DC Coupled. This refers to the coupling between the solar PV and the batteries, whether they connect to the system on the AC side or the DC side. Based on your power needs, site considerations and budget, we will help determine the best option, whether DC or AC coupled.

Off grid homes have no connection to the grid at all. This requires a lifestyle that most people in the U.S. aren’t used to, living without unlimited power on tap 24/7. Still thousands of people live this way because they make the right choices for it to be a viable lifestyle. If you aren’t willing to live without central heat and air, a dishwasher, and some other electrical energy appliances, you may want to reconsider. The biggest factor might be deciding if you want to understand electrical energy. A limited amount of understanding is vital to a successful system.

The solar power is stored in batteries and inverted with a special inverter that can also charge the batteries. Because more power is needed around the winter solstice, or December of each year, and this is also the period with the shortest days, most people use a generator during this period to assist the solar generation. Because the days are shorter, more light is needed. Because of wet and cold weather, people are inside more and using kitchen appliances, lighting, fans moving heat around, cooking, etc.

Myth: Off grid is cheaper than the electric company.

Sometimes people want to go off grid because its cheaper than the electric company. Wrong! If you want cheap, stay with the electric company. There are situations where the electric company wants say $50,000 to bring power lines to your remote location, and this can be a factor. If you have other reasons to get off the grid, plow ahead. Remember, you will be the plant operator and have full responsibility for your system, how much power you use and how you maintain it.

Off grid is easier with vacation homes, get away retreats, hunting cabins, etc. because they are not occupied 24/7 so you can save up power during the week for use on the weekend. The battery pack can be over sized relative to the PV to store electricity during the week for the weekends.

Which system is right for you?

Most of our installations are grid tied. Next is battery backup, and last is the occasional off grid system. Having trouble deciding? Our job is to help you pick the right type system for you. Contact us so we can help you get a system up and generating and join the rapidly growing group of fuel free solar power generators.