DIY Solar Power System Offers Easy Emergency Power Supply Read more: http://www.motherearthnews.com

[ashling]

How can I build a small solar power system for backup power during emergencies?

Putting together a system that provides enough solar power to run a few key appliances during a power outage is certainly possible — and it’s also a fun and educational project.

Small backup solar power systems consist of a photovoltaic (PV) panel or two to generate the electricity, a battery to store the energy, a charge controller to keep the PV panel from overcharging the battery, and an inverter that converts the battery voltage into regular 120-volt alternating-current (AC) house power. All of these parts are easy to find, and connecting them is simple and safe as long as you follow the instructions. (You can also tap into easy, DIY solar-powered lighting — read more at Easy DIY Solar Lighting.)

Many variations of DIY solar power systems are possible, but the table below will give you a starting point. The equipment brands I chose are just examples. The batteries in these systems are oversized to allow for poor sun conditions, and you should only drain the batteries to their minimum capacity if you are confident that power will be restored promptly. Some off-grid folks who are careful about power consumption live year-round on systems no larger than the “Larger system” outlined below.

One good way to find a set of components is to search online for RV or cabin PV systems. Many suppliers sell kits of compatible components in various sizes.

Read more: http://www.motherearthnews.com/renewable-energy/diy-solar-power-system-zb0z1302zsor.aspx#ixzz2peuVwunG

[hunter]

1. Lead acid batteries suck. You too can learn to hate them.

If you don't keep them topped up with power they die early. If you discharge them deeply or frequently they die early. Look at them the wrong way, they die early. Even when they work perfectly they don't last long.

Recycling batteries is a very messy business. Lead is very toxic. Even recently here in the U.S.A. battery recycling firms have polluted entire neighborhoods. In some nations lead acid battery recycling is an environmental nightmare and crime against humanity. Kids hack the batteries apart and the lead is melted down in open furnaces.

I have some solar panels I use for camping and, rarely, power emergencies. I don't use them often enough that it's worth dedicating a battery to them. I just use the battery in my old car. A "marine battery" works fine, so do the uninterruptible power supply batteries the IT industry sells off long before the batteries can be expected to fail. Then again, I don't live in a place where cold weather starting is an issue. I figure I have the damned car and the car battery anyways. Occasionally using it as a solar battery isn't going to hurt.

Most homes with solar power simply dump any excess power back into the power lines, but shut down entirely during power failures to protect line workers. That's because battery backup is expensive and often irritating.