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Renewable Energy in Spokane

Installing a renewable home energy system is good for the environment and can provide significant savings in home energy costs. That makes it a "win, win" or should I say "green, green".

Planning Your System

The first thin to consider when planning your renewable home energy system is if it will be a standalone system or a grid connected system. This will likely already be determined for you.

You may be investigating alternative energy systems because bringing grid power to your home site is not practical or it is cost prohibitive. If your energy needs require an off grid system you will need a system that will provide you energy at all times or you will need a way to store energy. On grid systems effectively store excess energy on the power grid to be used at a time when you need it.

Many incentive programs require that you are connected to the grid. Even when you are designing a grid-connected renewable home energy system, you may want to consider how effective it will be when there is a power loss. In this article I will focus primarily on grid-connected systems.

Next you will need to determine the size of system that you require. If you are adding a renewable home energy system to an existing grid-connected home than you can contact your utility company and they can give you your energy use history. If you are planning a system for an off grid home or a new build, it will take more calculating and estimation to come up with this information.

This is also a good time to consider ways to conserve energy. The initial cost of a home renewable energy system can be quite high and the greater your energy requirements are, the more expensive the system you will need. This is the time to consider options like high efficiency appliances, additional insolation, energy efficient windows and LED light bulbs. There are also incentive programs for many of these items.

The next step before you design your system is deciding which technology is best for your application. The options available are; solar electric systems, wind electric systems, micro-hydropower systems or hybrid solar wind systems.

Solar Panels

A photovoltaic or PV system uses solar panels that convert the light energy from the sun directly into electrical current. The basic system itself has no moving parts and has a very long expected lifespan. The solar panels generate direct current, (DC). Your home uses alternating current, (AC).

The panels are connected to a power inverter or micro-inverters to change the DC to AC that can be used by your home. Modern systems use micro-inverters so the power can be converted to 240 volt AC at the panels which is more efficient to move through wires over distance than low voltage DC.

Mounting your solar panels on a south facing pitched roof works well. These systems are most effective with direct sunlight but will still generate electricity with indirect sunlight or even overcast days. Warm days are not required; the panels actually are more efficient when they are cool. The Spokane area averages 171 sunny days per year therefore photovoltaic systems are a great option for Spokane.

Wind Powered Generators

If you live in a location where there are consistently steady moderate winds, a wind generator is be a good option. Wind generation may be the most cost effective alternative energy solution when comparing initial cost to power production capabilities. It is also capable of generating electricity day or night.

When you see wind farms one of the things that you may notice is that the towers are very tall. That is because there is more wind up high. The height of the tower adds to the expense of the system but it will pay for itself with the additional energy that it will generate. A 100 foot tower may add 10% cost to the whole system when compared to a 60 foot tower but when you consider that the 100 foot tower will generate 25% more energy, it is money well spent.

Even with the lower upfront cost of a wind system, because it has a lot of moving parts it is hard to predict how it will expense out over time.

Hybrid Renewable Systems

A hybrid system will normally consist of a solar panel array and a wind generator system. The advantage of this system is that the two energy production methods complement each other well. The peak times for wind generation are normally different from peak solar generation times. This makes this an ideal system for use off grid because it reduces the amount of power storage, (batteries) needed.

When connected to the power grid there is no real advantage to a hybrid system because during times of high production, you use the power grid to store the energy for later use. This will be explained more in "net metering". So it stands to reason to choose the one system that is best for your location that meets your needs.

Micro-Hydropower

As the name implies, micro-hydropower is a miniature hydroelectric power plant. The first thing that it requires is a running water source across the property. It should provide year round running water. If there is sufficient water flow throughout the year at all times of day, this makes an outstanding off-grid power source because there would be no need for a power storage system.

This system requires that you have sufficient drop in elevation of the flowing water from the point where it enters the property to the point where it exits the property. Ten feet or greater elevation drop is ideal but less than two feet won't work. So if you have a crick that flows across a narrow lot this is not an option. Most parcels would not support this type of system but if they do, this system is almost ideal.

Power Backup Systems

Even if you are on the grid, it would be nice to have a system that could provide you with electricity when there is a power failure. Systems designed for use on the grid are designed to shut down if they don't detect grid power. This is a safety precaution to protect the workers from the utility company who are trying to fix the problem.

Any solution for this is going to involve disconnecting the system from the grid and a power source. The power source could be a generator or a battery array with a converter/ inverter set up for charge and discharge. A camping generator or contractor’s generator is not going to have a clean enough 60 cycle signal to turn the micro-invertors on.

My solution is to connect a natural gas powered standby backup generator with a clean 60 cycle signal. It is connected through an automatic transfer switch to the main breaker panel. This automatically disconnects from the grid when the grid loses power and turns on the generator. The generator creates the signal that the micro-inverters need.

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