admin answers:

Don,

The noise made by a wind turbine has two sources. First is the actual rotation of the blades cutting through the air and the second is the mechanical noise of the gearing mechanism and generator housed within the nacelle (the white box on the top that houses the mechanics).

Nacelles are well insulated and you would have to be very close in order to hear the sound, so close in fact that even stood at the foot of the turbine you probably wouldn’t hear it.

Most of the noise comes from the turbine blades themselves, these are manufactured in such a way as to minimise noise impact. However, no matter how good the design there is always going to be some noise.

You didn’t say how far away the turbines are going to be from your vacation home, this makes a big difference. I’m assuming there will be several hundred metres, particularly as the windfarm will be offshore (in most countries there has to be a minimum distance between the turbines and any buildings).

The amount of noise that a modern turbine makes at a distance of 400 metres is about 35 dB(A)*, at 1000 metres it’s about 15 dB(A).

For comparison purposes 35 dB(A) is about the same noise that a quiet office air-conditioning system will make or the background noise inside a typical house (humming electrical items, heating system etc).

Given that the windfarm in question is going to be an offshore one, then I very much doubt you’ll hear anything. Partly because it will be some distance away and partly because any noise it makes will be masked by the sound of the sea itself.

I think I’d be more inclined to be concerned about the visual impact the turbines may have, and again, it depends very much on the distance. Some people find them to be aesthetically pleasing, personally I don’t.

One of the main factors that influenced our decision to move to where we now live was the view. We’re fortunate that the house overlooks rolling hills and green valleys with very little in the way of visual intrusion, if a windfarm were visible, even several miles away, I personally think it would have a significant impact. That however, is just my opinion, yours may be different.

* dB is short for decibel, it’s the measure of magnitude of pressure variation within the air. Environmental noise impacts are normally corrected to reflect the sensitivity of the human ear, this is what the (A) refers to.

admin answers:

Vertical wind generators are poor performers no matter how they are made.

There is a very recently published book that you should read called “Home brew Wind Power, and you can get it here http://www.otherpower.com .

You can also find a good review at http://www.rebelwolf.com/images/review.pdf

I was just about to write up a review on my web site – but found this question and thought I would save you a lot of grief.

The book title is perhaps a little misleading because it goes beyond what you’d consider “home brew”. These people have excellent engineering skills and their work is the state of the art.

These guys are serious — they work through the technical and physical design considerations (including discussions of vertical axis units) leading up to designs that actually work and even get into the detailed designs of creating the alternator from scratch. It also has links to an enormous amount of reference material.

You mention on buildings or around campus. Please be aware that the generator needs to be 30 feet above the buildings and the tallest trees to get decent power. Start by erecting an recording wind instrument on one of your existing communications towers (don’t get zapped) and find out how much wind you really have. Then calculate the maximum theoretical capacity using the equations in the book and you will find your answers.

admin answers:

Not charged by the method you describe. There would not be enough trickle charge to provide the charge in any meaningful time period.

But battery narrow boats do exist, its nothing new. There are a few on the Basingstoke and Montomery canals

You need a land line to charge up. Most have a diesel generator as well

Power is not a problem, the battery boats easily match the diesel powered boats for torque and control.

Its charging up every 2 days that will stop any chance of cruising around the system.

You get significant licence reductions for a battery boat.

admin answers:

Living on a boat is not for everyone. It is a lifestyle that can be great fun and very relaxed, but you have to work a little harder to be comfortable. Can you try it for a little while without having to make a committment?

You have to make arrangements for water and to have your holding tank pumped out. Most people go ashore for water – sometimes to a marina dock. In a very few places there is water delivery to boats, but in my experience that is not the norm. I have never seen that happen. When we anchored for longer periods my husband and I often dinghied 5 gallon jugs of water back to our boat on a regular basis – every time we went ashore.

What about power? Do you want to have electricity? If so, you need to think about wind generators or solar panels, depending on where you live. How about refrigeration? That is the biggest consumer of energy on a boat. There are options that use less power, but they tend to be more expensive. Do you want to be able to have a hot water shower on the boat? Is it hot enough where you live to use a solar bag/sun shower to heat your shower water each day or will you need a water heater?

How about cooking? If you have a propane stove, especially a Force 10, two burner with oven, that will be great, and many people also have a BBQ in the cockpit. With propane you should have a propane detector in your cabin and bilge as propane sinks if it is leaking, and could collect in the bottom of your boat and cause an explosion.

If you anchor, you have to dinghy ashore everyday. You may need to lock your dinghy when you go ashore, depending on where you are anchored. Will you have a vehicle on shore? If so, that will make life easier, as you will not have to backpack laundry, groceries, etc. If you are depending on getting ashore by dinghy to get to a job, what about the days when it might be too rough to get the dinghy ashore?

Do you want to have TV and Internet on your boat? We used a cell phone to have Internet access when we were anchored. Sometimes we were fortunate enough to be able to receive an unsecured wireless signal. For TV, you might be able to receive the free channels from you boat if you put an antenna high enough. The reception will of course vary with the movement of the boat.

Depending on your location, you may need to protect all you clothing from humidity and mildew. We rolled all of ours and packaged everything in airtight ziploc bags to keep the moisture out.

Some people who live on boats choose to rent a slip at a marina and then they can have most of the conveniences of a land based home while living on a boat. Not all marinas allow live aboards.

I would live on a boat again in a flash if the opportunity presented itself with the right person. My husband and I enjoyed it immensely and had wonderful adventures. We were happy vagabonds. We were both retired though, so we did not have to worry about getting ashore for work, etc.

So I hope I have given you some food for thought. Most people I know who live on boats and work ashore actually live in a slip at a marina, but I also know a few who anchor and dinghy ashore everyday to a job. Best of luck with you plans. I would do it. Feel free to ask about anything else you think I could help with.

admin answers:

The answer is that the mpg would decrease–probably by a lot. The reason is that the gas engine will have to create the wind to run the wind turbine. So basically you’re going to have an energy conversion losses by converting from gas to wind to electricity. But it will be worse than that because there is also the additional drag of the wind turbine parts.

I don’t know what kind of wind turbine you could use.

Now what would work is to add battery packs to the Prius and have a stationary wind turbine charge these packs. However, because the Prius battery packs are over 200V it’s not a safe thing to do unless you are qualified to work on high voltage equipment. There is also the battery ECU to worry about. Somehow you will need to tell it what you are putting into it.

admin answers:

Hey Kevin, I think people are avoiding answering this because the question is too nebulous, I’ll explain. 25,000 kwh per year, or about 2000 per month is quite a larege number for a residence, are you running a business? Our home uses 300 – 350 per month, a bit below the average for a 2400 square foot single family dwelling. Trying to get answers on this with usage and average wind speed is like me asking you what kind of car should I get, I live about 12 km from work. Any car can get there, but do I need cargo space, winter driving capabilities, do I have kids? And so on. We use a 900 watt Southwest Windpower model H-40, it is probably a bit too small for our home, something on the order of 1500 watts would work better, but we over did the solar array at 1.4kw, and in the end we make about 90% of our electricity, the other part comes from the power company.

Wind turbine output is a function of the cube of the wind speed. If you double the wind speed, you can theoretically get 8 times the power out of the turbine. But then some turbines have ideal design wind speed higher than others, so a lighter wind turbine in heavy winds will actually degrade from its power curve on a good day. Our site has really good wind in the fall and winter, and really good sun in the spring and summer, so solar and wind complement each other here. This is basically true of most places, just getting the turbine might be disappointing in the end. Three bladed units work better in gusty shifting winds, but are less efficient in lighter winds than 2 bladed ones. When you say your average wind speed is 20 mph, is it 20 most the time, or 5 mph for 3 days, then 40 mph on day 4? This makes a big difference in turbine selection.

What I’m really getting at is this isn’t a question for hacks like me online. In the 12 years we have been using solar and wind power, and teaching renewable energy at our local schools, I’ve learned that there are three things in vast supply, sun, wind, and missinformation. There are better ways to get informed on this subject than here, I will list some sources below to start you out. My first suggestion is to get a subscription to Home Power Magazine. They are the only periodical that get into the nuts and bolts of this subject. Then when the first issue arrrives, look in the calendar section for an energy fair near you. We subscribed 13 years ago, and went to the fair in Wisconsin in June that same year. Here we are today. It would be so easy for someone like yourself to buy into a machine that does not work well for your site, but works very well for the installer to make money with, trust me on this.

Check out the sources below, try to make one of the energy fairs, and then you’ll be in a position to ask some really good questions. Good luck Kevin, and take care, Rudydoo