Green Power Components

Every home power system is different. Are you using batteries? Is your system grid-linked? Do you need to be able to disconnect it if too much power is being generated? These needs will determine what components you need.

Let's start basic:

Green Power Generators

The first step in any green power system is a solar panel, wind turbine, or micro-hydro generator (there are a few others, but I'm not really working on them right now).

So the first question is: what are you going to pick out?

1. A Solar Panel
2. A Wind Turbine
3. A Micro-Hydro Generator

Battery-Linked Systems

Things get a little hairier here. So let's keep it simple and go through step-by-step.

If you are going to have batteries, you will need:

1. Batteries
2. A charge controller
3. A heat sink (maybe)

At least the first two of these deserve their own section. At the time of publication, those sections have not yet been written. In short, the batteries need to be high quality batteries- these are the work horses of a battery-linked system. There are various kinds, sizes, and arrangements for the batteries. But they have to be selected carefully and treated with care. Please note, though, that you will need deep cycle batteries- they look a lot like car batteries, but function very differently. They are very heavy, charge more slowly, and can be much more fully discharged than a car battery.

Charge controllers are seemingly unremarkable, but they are utterly critical. If you're going to care for your batteries, you have to have one, and it's not a place to skimp. This little box is actually a quite complicated piece of machinery. It ensures that your batteris are never overcharged and disconnects them from the power generator (solar panel/wind turbine) when they are full. It's actually quite an impressive feat. More on that in its own section.

Inverters

The heart of a grid-linked system is the inverter. The inverter changes the power coming off your batteries or directly off your solar panel or wind turbine and convert it. Your home, and your electrical grid, function on AC (altered current) power and wind turbines, solar panels, and batteries function on DC (direct current) power. The inverter takes the power coming in as DC power and makes it AC power.

It is worth noting that if you are tying directly into a grid, you will need a special "grid-tie inverter." Before purchasing a grid-tie inverter call your power company. They may have specific features that they want to a grid-tie inverter to have- and it would be terrible to have the system all ready to go and then have to take if off-line because the electrical code won't let you.

An inverter is also necessary if you are fully off-grid. You still need to power your appliances and anything else you may want to power using AC power- and the power coming from your renewable energy system is still DC power. The requirements will be more determined by the nature of your system than by electrical company code, but it is still a necessary component.

DC Disconnects

The DC disconnect sits between a bank of batteries and the inverter. It is essentially a protection device. It's almost like a giant surge protector. If there is ever a malfunction in the battery wiring or some kind of short, it can discharge far too much electricity to the inverter. This can destroy the inverter and possibly some of the appliances in your house. Thus, the DC disconnect monitors the flow of power from your battery pack and disconnects the inverter from the batteries if there is ever a dangerous surge in power.