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Free Energy from the Sun and Wind

"Free Energy" is perhaps a slightly misleading title.

The electrical energy from solar panels and wind generators only becomes free after an initial investment in the equipment.

However, after that initial investment, the word “free” really begins to take on a huge significance.

The cost and of both solar and wind generators has dropped considerably in the last decade while their efficiency has improved.

But which is the best system for you, a Wind Generator or Solar Panels or should you invest in both?


Which free energy source is better, Wind Power or Solar Panels?

Well both types have advantages and disadvantages.

And apart from anything else, wind generators need plenty of wind and solar panels need lots of sun.

Perhaps the optimum answer is to have both but so much depends on your specific situation and needs.

But whichever free energy source you chose, it will free you from both the cost of and the pollution caused by running your engine to charge your batteries.

It frees your engine from the wear and excessive build-up on valves etc. that running an engine just to charge batteries can cause.

Solar energy is also noiseless and many of the newer types of wind generator are virtually noise free.

There is also the freedom from worrying about flat batteries in an emergency. 

Just a few hours charging can even give enough charge to start the engine.

For those with no onboard charging, it frees you from having to haul that heavy battery ashore for charging.

And you can boat totally independent of shore power or fuel.

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Energy Needs

Looking for a Solar Panel?
Looking for a Wind Turbine?

Even when you are able to generate your own free energy using either solar, wind power or both, reducing the drain on the battery bank is easier than keeping them topped up.

Huge savings can be made in energy needs by a careful choice of the devices to be powered,

Improving the efficiency of lighting by fitting LED bulbs can make substantial reductions to the lighting load, especially LED navigation lights that often run for long periods on a night passage.

An LED can run all night on the same amount of energy that a standard halogen bulb would use in one hour.

Strong, dependable batteries are the foundation of any boat electrical system.

And a good monitoring device will allow you to see exactly what's happening in your system at any given time.

For twin battery banks an automatic two-way split charge relay is recommend to allow the battery banks to charge as one but discharge separately.

Improvements in power efficiency can lead to the need for a smaller battery bank that will need smaller solar panels and smaller wind turbines to keep it charged.

“I grew to judge every purchase by how many bronze screws I could buy for the boat if I didn't spend on this or made do without that.”
(Lin Pardey)

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Charging Needs

How much of that free energy you need will clearly depend on how you use your boat.

A liveaboard will want a constant supply of free energy on a daily basis.

And the liveaboard will probably want a both wind and solar to capture the best of both systems.

However, the owner who only uses his boat at weekends could make do with a relatively small solar panel that can take all week, if necessary, to recharge the batteries.

Quite often finding a suitable position for the generator, of either type, on a boat is the biggest problem.

There are portable solar generators that combine solar panels and controllers in a single package.

These days there are numerous gadgets such as flashlights, radios, vents and fans that have their own built-in solar panels.

And there are also the small portable solar chargers for phones etc.

Rdk Products Marine-grade 2000 Watt Wind Turbine

Rdk Products Marine-grade 2000 Watt Wind Turbine

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Free Energy Comparisons

Solar Pannels Wind Turbines
Solar panels, including the charge controller and mounting hardware, are generally less expensive than a wind generator. Wind generators are more expensive.

And they require a substantial mounting framework that can add to the cost.
Solar panels require little maintenance and can last for many years.

Many panels are almost unbreakable.
Wind generators are mechanical devices so a certain amount of maintenance is required.
The negative side to solar panels is the 'effective' charging time, space required, and problems with shadows on a sailboat.
While a solar panel can generate electricity during the daytime when the wind is not blowing, a wind turbine can generate electricity all night too, as long as there is a breeze.
Wind turbines tend to be more location sensitive than solar panels.

They need to be situated in an area of above average wind in order to generate reasonable amounts of power.

They also require a smooth airflow, turbulent air will have the turbine constantly changing direction, chasing the wind rather than extracting power from it.

Whereas most people can implement a small solar array in most locations and achieve success, the same cannot be said about turbines.
Solar panels are completely safe. There is a potential safety factor concerning the danger from those rotating blades if they are properly maintained.
No noise. Some wind generators can be noisy.

Most panels can stay out in practically any weather.
Some wind generators are self-regulating in high winds.

Others require shutting down manually and the blades tying off.

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I am perfectly aware that the majority of Wooden Boat aficionados are sensible folk.
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