Dependable off-grid systems are essential for surviving without a utility company as your electricity provider. There are four primary parts to every off-grid system: 1) A device to capture the renewable energy source, whether it be sun, wind or water, 2) The battery based inverter to provide stable electricity for home appliances 3) The proper amount of energy storage, usually batteries and 4) An engine driven generator for times when wind power and solar power are not available.
RENEWABLE ENERGY SOURCES
Wind and solar are the two main energy sources, but others like micro hydro and biofuels are increasing in popularity. Energy Options offers several wind turbines and solar electric panels for battery charging. Each device needs a charge controller to optimize the current going to the batteries. The charge controller is an essential part of each generating device. It is a common misconception that an off-grid home runs on these devices. Actually it runs on the batteries and these devices are merely battery chargers. Energy Options can calculate how large of a system you need for your home at no charge.
BATTERY BASED INVERTERS
Battery based inverters are very different than grid connected inverters. Outback Power and Xantrex are the main two off-grid inverter brands offered by Energy Options. The Outback VFX3648 is one of the most dependable and reliable battery based inverters on the market. They can be joined in sets up to 10. The combined inverter capacity is up to 36kW at 120/240 volts. Coupled with Outback’s Mate any user can remotely keep track of their energy production, battery capacity and automatic generator controls. Xantrex also has a complete line of off-grid inverters that can operate independently or be joined for greater capacity. Xantrex has been a leader in the off-grid inverter market for years and builds long lasting, dependable products.
Most batteries used in renewable energy applications are standard lead acid deep cycle batteries. A golf cart battery is an example of a small deep cycle battery. A car battery is not a deep cycle battery. This technology has not changed much in the last 50 years. These batteries require regular maintenance and watering. Two new technology batteries are sealed, low maintenance batteries. They do not require adding water, but they cost about twice as much as standard deep cycle batteries.
There are two ways to build sealed, low maintenance batteries: absorbed gas mat (AGM) and Gel cells. Both claim that their way is superior. We sell both kinds. AGM batteries use a fiberglass-like material between the cells to hold the liquid electrolyte. AGM batteries are by far the most common sealed battery type, are easier to make, generally cost a bit less than gels, and because their electrolyte is more liquid, can tolerate higher charge and discharge rates. But because they are almost starved for electrolyte, AGM cells are more easily damaged by overcharging. They can’t afford to lose any water. This requires a top quality charge controller and accurate programming. Gel cells use a jellied electrolyte with more liquid content and are more tolerant of the occasional overcharge. But they absolutely must be assembled without any air bubbles or voids, so they cost more to build. The extra cost may be off set in life expectancy, with gels usually lasting 20% to 30% longer regardless of the cycle depth.
Rolls Surrette, Trojan, Hawker Industrial, Concorde, and Interstate are a few of the many batteries that Energy Options sells. Some of these batteries weigh over 1,000 lbs each. A common off-grid home uses eight Trojan L-16 batteries. They cost about $420 each. Understanding the load requirements and calculating battery size is critical to building a dependable system. Energy Options has customized software to properly evaluate each customer’s needs and provide the proper sized system.
ENGINE DRIVEN GENERATORS
Whether you are grid connected or off-grid, a backup generator is ideal for back-up energy in adverse conditions. Energy Options offers the Kohler line of pad installed generators for any size home or business. Available in 8.5kW to 100kW output, Kohler generators provide worry-free emergency power to supply your total electrical needs for days, or even weeks. Unlike portable generators that require refueling every few hours, Kohler backup power systems can be fueled by a permanent LP or a natural gas connection. These engines come standard with an interface that allows them to be started and stopped by the inverter’s programming. It makes them automatic. The Kolher products are much quieter than the common ones.
GRID CONNECTED BATTERY BACKUP SYSTEMS
Energy Options offers a variety of grid-tied emergency battery backup systems. These systems will pay for themselves. Standard back-up systems will never pay for themselves because they only work in an emergency situation. Back-up systems that are powered by wind and solar allow power to flow back to the utility in non-emergency times thus saving money and paying for themselves. In an emergency they instantly change states and supply electricity when the utility company fails. Wind and solar incentives apply to the whole system, but standard back-up power does not qualify for either tax credits or special renewable incentives. A renewable back-up power system is a better deal than just a standby generator or a standard uninterruptible power supply.
One of the most common grid connected battery back-up systems is OutBack’s PS1. It functions like a standard uninterrupted power supply (UPS) except it is powered by wind or solar. It uses a 3.6kW inverter, the GVFX3648. Energy Options also caries Xantrex backup systems.