Many people dream of escaping the stress, noise and pollution of the modern urban environment. The dream of off grid living is one of peace and tranquillity, and rediscovering a spiritual connection to the natural rhythms of the earth. However, establishing a sustainable, comfortable and safe off the grid living situation is no easy task.
Of critical importance in any off the grid living plan is the means for achieving self-sufficiency in electricity. Solar panels are the obvious choice for most people in this situation, but identifying the right system and set-up takes some knowledge and experience. In this article we will outline some of the factors that need to be considered when planning for your off-grid power supply to help you get a feel for just what off the grid power systems involve.
Solar Power: The Absolute Basics
Solar power is based on a “photo-voltaic” system that uses panels to convert direct sunlight into electricity, a set of solar batteries for storing electricity for when there is no sunshine, a charge controller that prevents the solar batteries from overcharging and an inverter that turns low voltage DC power into regular 120 or 240 volt residential current.
Solar Power: The Components
• Solar Panels
There are a number of different ways to mount your solar panels. These methods include panels that are fixed to your roof, panels that are fixed into the ground, panels that are fixed onto mounts on a pole, or panels that are mounted on tracking arrays. Roof-mounted panels are the safest and most convenient, and can help keep roof temperatures down, but they do not work in climates with significant snowfall. If you choose to place them on the ground or mount them on a pole, then you can adjust them seasonally to maximize power intake. The average solar panel is around 40 pounds and 40 by 60 inches, so you need to keep that in mind when planning for your solar set-up.
• Charge Controller
The solar panels themselves will be wired to your charge controller. The controller ensures that the batteries are supplied with the appropriate volume of power, and that they can handle the rate, which will help make sure that your batteries have a long life. The usual solar set-up has one solar panel, one charge controller and one battery.
Most of the batteries used for off-grid power are a flooded lead acid type battery. They have caps with vents, discharge hydrogen while charging, and they need to be vented and re-watered often while they are charging.
Another popular option is an AGM battery, which does not require venting. It is also completely sealed, so does not to be watered. Another added bonus is that it will not leak acid if it is damaged. However, it is more expensive than the traditional lead acid battery.
The inverter is what transforms your low voltage DC into useful 120v AC for your household power needs. There are a huge range of inverters, from cheap Black and Decker versions that you can buy at Walmart to top-of-the-line Xantrex or outback models that have an integrated battery charger and can even be connected to a diesel generator. The cheapest inverters need to be connected to each appliance, while the higher-end version can be installed directly to your breaker panel.
• Breakers, Fuses and Disconnects
For convenience and safety you will want to install fused disconnects between each of the solar panels and their charge controllers, between each of the charge controllers and their batteries, and between each of the batteries and your inverter. This set-up allows you to safely isolate each different component for regular maintenance, and to automatically disconnect each component in the case of an electrical short or malfunctioning equipment.
• Battery Monitor
Without a battery monitor you will have no idea what your energy levels are until your power runs right out, and then you will be in a serious situation. The simplest yet least effective system is a volt meter. This will tell you the voltage of your batteries, but the reading will be skewed by how often you charge and discharge the batteries. The most popular method is to use an amp hour meter, which shows the amp hours in deposit and the amp hours withdrawn.
Solar Power: The Cost
Of course, what you really want to know about all of these different components is how much they are going to cost you.
The standard off-grid system usually consists of one solar panel ($550), one charge controller ($100), one marine deep-cycle battery ($160), and one inverter ($60). After adding the various additional components like fuses, connectors and wiring, the whole thing should run you around $1000. This system will power a few lights, your radio and a small pump for water.
The more advanced set-up will usually involve two panels ($1100), a better charge controller ($150), two batteries ($300), and a high-end inverter/charger ($1700). Adding the miscellaneous extra costs to this more advanced system will probably cost over $3300. However, this would power computers, televisions and powerful appliances like microwaves.
Past this point, the cost will scale with the amount of panels you add to the system. Once you have paid for the high-end inverter/charger, it is only a matter of adding panels, controllers and batteries.
Solar Power and Appropriate Energy Use
Part of the appeal of off-grid living is the simplicity and the return to nature. Even if you can set up a large and expensive solar panel field, the idea of off-grid living is to reduce your consumption to basic needs. You can use propane-powered appliances, such as stoves, water heaters, refrigerators, dryers and furnaces. However, you can go even further by reducing your propane reliance as well. You can use wood heat for cooking and washing, you can dry clothes naturally, you can harvest rainwater and you can use composting toilets, among other possibilities.
Solar Panels, Self-Sufficiency and Off-Grid Living
Living off-grid is never easy, but it can be simple. A solar power system for your electricity needs is an absolutely essential part of your off-grid plan. However, how expensive and complicated the system needs to be is entirely up to you. The key is to plan out your power needs well from the start, and then install the system that is just right for your specific needs.
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