When the Grid Goes Down, Go Solar?

Guest Blog: Thomas Hoekman is a student at McGill University and an intern at SolarTown this summer. Thomas has been spending a lot of time this summer researching solar batteries. When Thomas was left without power due to the recent storms in the Washington, DC area, he had to become a quick study in living life off the grid. We have blogged before about the kind of solar energy products that may help you in an emergency, but living without power made this issue much more personal to Thomas. We asked Thomas to blog about his off grid experience and what solar solutions may help in the event of another emergency.

A couple weeks ago, I spent a lot of time overheating in my dark, humid house with fond memories of air conditioning to to keep me company. Ironically, this year’s Independence Day reminded me of just how dependent I am on grid power. Without it I lost AC, water, and several hours of each day. I know I wasn’t the only one this happened to. This year’s power outages affected hundreds of thousands of people and in Virginia almost one million households lost their power.

My home does not have a backup generator and, until recently, was only stocked with just one flashlight. In hindsight this was not a good decision. Since we as a nation probably won’t upgrade our infrastructure, power outages are going to continue to happen. This is especially true considering that some scientists have linked extreme weather last year to climate change. In order to be more prepared for the next outage I’ve decided to get a backup system. I have two main choices: diesel and solar.

Diesel generators are by far the more common choice for backup systems. Hospitals, businesses and many homes use them because they are reliable and relatively cheap. They also have large capacities, so it is not too hard to power your entire house during a power outage. However, diesel is a polluting, expensive fuel and diesel generators need to be cared for if you want them to work. The last thing I want is to invest heavily in a generator only to have it fail five years later when there is a power outage. I heard this happened a few times last month. So is solar a better option?

A solar backup system is probably a lot more expensive than a diesel generator. You have to buy solar panels, a solar inverter, a charge controller, and a solar battery bank. Fortunately the running costs are much lower. You don’t need fuel in a solar system! Despite this fact, it is unlikely that fuel costs will match the price of replacing old batteries. Solar is going to be more expensive, at least up front.

Another possible advantage is on the maintenance side of things. AGM batteries are very durable batteries that can hold a static charge for a long time. SolarTown has AGM batteries that can last 8 years without being replaced. This makes them perfect for a backup battery bank. You can install them, forget about them for a while, and still have them in good working order. Of course they should be trickle charged like all batteries, but the solar panels will be doing just that. Trickle charging makes sure the batteries are always topped off, preventing sulphation and other kinds of damage. Diesel generators on the other hand need to be ‘exercised’ regularly to make sure they are in working order. And don’t forget about changing the oil, coolant, etc.

Finally, a solar backup system can also be grid tied, and thus contribute to lowering my electricity costs year round. By adding a battery bank to a regular panel setup you could get clean and reliable energy all the time, even during blackouts. A properly designed solar backup system thus has some practical and environmental benefits over a diesel generator. Another option I haven’t even explored yet is combining the two technologies. At the end of the day the question remains: Is a backup system worth the extra price?