As the user of a mooring, and not a dock with shore power, i would love to get some feedback on alternate power sources. I've looked at both wind and solar- both can be expensive- so both is no an option for me. I understand the advantages of both sources- but if i had to choose- what is better? cheaper? easier to install? basic amp hours needed for mainly weekend getaways?...Also..what are the components needed away from the generator itself?, just a charge controller? What rating should i get on that unit? looking for any direction- and recommendations....
wind vs solar power generation
- Thread starter ken6736
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when the wind blows...
Often, the sun isn’t out, and when the sun is out, the wind often doesn’t blow. I have found, through designing many renewable energy powered land sites, that a combo of both is best. Now, that said, if I was to make a choice, I would go with a wind turbine first such as an Air-X Marine, and then add a 120-200 watt solar panel in the future. The Air-X has a built in charge controller that you can use, and it is easy to set up. If you go Solar, you will need a charge controller of the right size, but they can be had for ~ 65 for a so-so one. here’s a nice site I buy stuff from: http://store.solar-electric.com/chco.html
Often, the sun isn’t out, and when the sun is out, the wind often doesn’t blow. I have found, through designing many renewable energy powered land sites, that a combo of both is best. Now, that said, if I was to make a choice, I would go with a wind turbine first such as an Air-X Marine, and then add a 120-200 watt solar panel in the future. The Air-X has a built in charge controller that you can use, and it is easy to set up. If you go Solar, you will need a charge controller of the right size, but they can be had for ~ 65 for a so-so one. here’s a nice site I buy stuff from: http://store.solar-electric.com/chco.html
Depends
It depends on the area you are in some areas have better wind or more sunshine. If you live in an area where the wind drops during the day and at night (like the Chesapeake Bay in the summer) you may not get the required wind to generate. Wind gens usually need 10 knots or more to get good output. I would recommend looking at the best sources of wind or sun to determine which application would be the most effective. Search the archives, this has been a popular discussion. Me I like solar....
It depends on the area you are in some areas have better wind or more sunshine. If you live in an area where the wind drops during the day and at night (like the Chesapeake Bay in the summer) you may not get the required wind to generate. Wind gens usually need 10 knots or more to get good output. I would recommend looking at the best sources of wind or sun to determine which application would be the most effective. Search the archives, this has been a popular discussion. Me I like solar....
Another Consideration
Morning Ken: What systems to you have running when your away from the boat and how big is your battery bank? Try and figure out what your amp hour usage is while your away from the boat and make your decision based on that information. You might not need as much as you think you do. If what ever system you decide on doesn't have a charge controller(regulator), you'll definately need one or you can cook your batteries dry. They are not that expensive.
Morning Ken: What systems to you have running when your away from the boat and how big is your battery bank? Try and figure out what your amp hour usage is while your away from the boat and make your decision based on that information. You might not need as much as you think you do. If what ever system you decide on doesn't have a charge controller(regulator), you'll definately need one or you can cook your batteries dry. They are not that expensive.
First Calculate your needs
The first step is to calculate your needs. If your boat is a Catalina 22 with VHF and Depth sounder used a couple weekends a month for daysailing think small solar. Maybe an outboard with a small generator. A larger boat with a diesel may be able to get by with an extra battery and high output alternator. I say solar because the panels are maintenance free and may easily last 20 years. If you have a lot of demand then a combination of charging sources will be required. Some have to have their microwave and air conditioner and water maker and stereo and computer and color TV.... I like to keep it simple. When we kept our boat on a mooring I just took the battery home for charging. Yep it was a pain to get it home and back but it cost nothing as I already had a battery charger. Tom
The first step is to calculate your needs. If your boat is a Catalina 22 with VHF and Depth sounder used a couple weekends a month for daysailing think small solar. Maybe an outboard with a small generator. A larger boat with a diesel may be able to get by with an extra battery and high output alternator. I say solar because the panels are maintenance free and may easily last 20 years. If you have a lot of demand then a combination of charging sources will be required. Some have to have their microwave and air conditioner and water maker and stereo and computer and color TV.... I like to keep it simple. When we kept our boat on a mooring I just took the battery home for charging. Yep it was a pain to get it home and back but it cost nothing as I already had a battery charger. Tom
Amps
I've been looking at the ads for Solor and wind generators and all they talk about is watts and volts. Doesn't say anything about amps. Isn't that what I really need to know to determine the capability of the charger? If so, any good links on these that give an AMP layout?
I've been looking at the ads for Solor and wind generators and all they talk about is watts and volts. Doesn't say anything about amps. Isn't that what I really need to know to determine the capability of the charger? If so, any good links on these that give an AMP layout?
volts times amps equals watts
So a 100 watt panel will provide 8.3 amps at 12 volts. Optimal charging of a wet cell is 14.4 volts so your 100 watt would provide only 6.9 amps. Then you have resistence that will drop your voltage. Tom
So a 100 watt panel will provide 8.3 amps at 12 volts. Optimal charging of a wet cell is 14.4 volts so your 100 watt would provide only 6.9 amps. Then you have resistence that will drop your voltage. Tom
By the Hour?
Ok...now, is that by the hour? When they say 100 watts, is that per hour or minute or second or day? I ask because I've been estimated that I will burn about 145 amps a day and need to charge that back. Like on the link below, it says how many watts for a given wind speed, but it doesn't say what the time frame is. Ex: Output: 400 watts at 28 mph (12.5 m/s)
Ok...now, is that by the hour? When they say 100 watts, is that per hour or minute or second or day? I ask because I've been estimated that I will burn about 145 amps a day and need to charge that back. Like on the link below, it says how many watts for a given wind speed, but it doesn't say what the time frame is. Ex: Output: 400 watts at 28 mph (12.5 m/s)
Watts is per second
Amps is a given number of electrons. Usually time is given such as amp/hours Equals one amp/sec for an hour.
Amps is a given number of electrons. Usually time is given such as amp/hours Equals one amp/sec for an hour.
80 Watts with a controller
I have an eighty Watt solar panel which I use basically to charge my house batteries as well as starting Battery. I have no shore power at my dock and I never have a problem. If I require additional charge due to using to much stuff I will allow my engine to get me back up to par. I have intentionally allow my batteries to discharge to see how long it would take to recharge. It took approximately 4 to 6 hours and I could start my 18 HP motor. Bottom line, I would not have a boat without solar power.
I have an eighty Watt solar panel which I use basically to charge my house batteries as well as starting Battery. I have no shore power at my dock and I never have a problem. If I require additional charge due to using to much stuff I will allow my engine to get me back up to par. I have intentionally allow my batteries to discharge to see how long it would take to recharge. It took approximately 4 to 6 hours and I could start my 18 HP motor. Bottom line, I would not have a boat without solar power.
One thing about Solar,
I would highly recommend that you get panels that have a blocking diode on each cell, this way if a shadow falls on the panel, it wont take the whole panel out. Uni-Solar is good for this. Plus, you can slightly bend these panels (they are doped on a steel sheet backer, no glass) to form fit your boat, or you can get the fully flexible panels to fit anywhere.
I would highly recommend that you get panels that have a blocking diode on each cell, this way if a shadow falls on the panel, it wont take the whole panel out. Uni-Solar is good for this. Plus, you can slightly bend these panels (they are doped on a steel sheet backer, no glass) to form fit your boat, or you can get the fully flexible panels to fit anywhere.
Correction to p323ms' definitions.
Electric "charge" is related to "number of electrons" and is measured in coulombs. Current (in amperes) is the rate of flow of charge, that is a current of one amp is equivalent to a flow of charge of one coulomb per second. Power (measured in watts) is a measure of the rate of flow of energy, which in electrical terms is voltage x current. "Ampere-hours" is another measure of charge (usually applied to battery capacity and discharge) and corresponds to a current of one amp flowing for one hour. Similarly "watt-hours" is a measure of energy. These two are related: in a 12 volt system 12 watt-hours is equivalent to 1 amp-hour. (Note that I said equivalent, not equal, because they are different physical quantities). The term amps/sec has no physical meaning. Now regarding solar cells - the manufacturers rated power is the maximum you will get under ideal conditions (sun directly overhead, no clouds, no shadows). The real world ain't really like that, and the total charge you will get on a given day (measured in amp-hours or watt-hours) will be way less than you might think.
Electric "charge" is related to "number of electrons" and is measured in coulombs. Current (in amperes) is the rate of flow of charge, that is a current of one amp is equivalent to a flow of charge of one coulomb per second. Power (measured in watts) is a measure of the rate of flow of energy, which in electrical terms is voltage x current. "Ampere-hours" is another measure of charge (usually applied to battery capacity and discharge) and corresponds to a current of one amp flowing for one hour. Similarly "watt-hours" is a measure of energy. These two are related: in a 12 volt system 12 watt-hours is equivalent to 1 amp-hour. (Note that I said equivalent, not equal, because they are different physical quantities). The term amps/sec has no physical meaning. Now regarding solar cells - the manufacturers rated power is the maximum you will get under ideal conditions (sun directly overhead, no clouds, no shadows). The real world ain't really like that, and the total charge you will get on a given day (measured in amp-hours or watt-hours) will be way less than you might think.
Diode on Each Cell
Generally when a cell has a shadow over it, it will just not put out as much voltage. Even in a shadow, it will contribute. I can understand putting a diode on the whole system or even a diode on each string, but not on each cell.
Generally when a cell has a shadow over it, it will just not put out as much voltage. Even in a shadow, it will contribute. I can understand putting a diode on the whole system or even a diode on each string, but not on each cell.
Amps/Amp Hours/Watts
An amp is so many electrons/sec. An amp-hour is one amp for one hour. A watt is amps times volts. A watt hour is one watt for one hour.
An amp is so many electrons/sec. An amp-hour is one amp for one hour. A watt is amps times volts. A watt hour is one watt for one hour.
Some answers about Watt, VA, Watt/Hour
Question from Franklin.. The win-gen you refer to can be set for 12v or 24v system so it rate its output as 400w(at any moment at given wind speed). Which means, when set at 12v it will put out 400/12=33A of current. When set at 24v the current will be half, 16.5A. In case of AC system or when inductive load is in a system then the term VA also used. VA is voltage mutiply current(VA) a power source can supply or a inductive load would absorb and the Watt is actual power really used by the load and convert it to physical force. Watt=VA x efficency factor indicated on the equipment(must >80%, as far as I know) In pure resistance(light bulbs)load, VA is equal Watt regardless it's AC or DC power source Watt Hour is merely describ how many watts is used in an hour so the power company can charge accordingly. Or how many hours a house battery would last. Hope this will help.
Question from Franklin.. The win-gen you refer to can be set for 12v or 24v system so it rate its output as 400w(at any moment at given wind speed). Which means, when set at 12v it will put out 400/12=33A of current. When set at 24v the current will be half, 16.5A. In case of AC system or when inductive load is in a system then the term VA also used. VA is voltage mutiply current(VA) a power source can supply or a inductive load would absorb and the Watt is actual power really used by the load and convert it to physical force. Watt=VA x efficency factor indicated on the equipment(must >80%, as far as I know) In pure resistance(light bulbs)load, VA is equal Watt regardless it's AC or DC power source Watt Hour is merely describ how many watts is used in an hour so the power company can charge accordingly. Or how many hours a house battery would last. Hope this will help.
Not really
This is what I need to know. If I am using 145 amps in a day, what percentage of those amps would be recharged if I was running a wind generator that was putting out 400 watts at 28 mph winds? See...I'm missing some piece of information. I know (well...actually a guess from another poster) that I will burn an average of 145 amps in 24 hours. 400w/ 12v = 33.33 amps. But is that per second, per minute per hour, or per day? If it's 33.33 amps per hour, then 33.33amp x 24hours = 800 amps in a day. That doesn't sound right. Sure, that's at 28 mph winds. Lets take 14 mph winds. The scale says it will produce 58 watts. So that comes out to 116 amps a day it will produce. Still sounds a little high to me. Is it?
This is what I need to know. If I am using 145 amps in a day, what percentage of those amps would be recharged if I was running a wind generator that was putting out 400 watts at 28 mph winds? See...I'm missing some piece of information. I know (well...actually a guess from another poster) that I will burn an average of 145 amps in 24 hours. 400w/ 12v = 33.33 amps. But is that per second, per minute per hour, or per day? If it's 33.33 amps per hour, then 33.33amp x 24hours = 800 amps in a day. That doesn't sound right. Sure, that's at 28 mph winds. Lets take 14 mph winds. The scale says it will produce 58 watts. So that comes out to 116 amps a day it will produce. Still sounds a little high to me. Is it?
putting a diode on each
cell enables the panel to put out charging voltage even if most of it is in the shade. (if the panel has been made for it) I’ve put in a few dozen solar power systems in remote locations (i was a Radio tower ground tech) and a few boats, it does have a good performance improvement if there is something around to cast shade on the panel. Since doped panels mostly have them built in, it’s a no brainier in my book for marine usage. Almost on any panel not made for it, if there is as little as one cell shaded, it will cause a severe drop in power. BTW, im certified in solar power installations (but not wind, but ive done them too). Also a highly recommended reading resource is Home Power Magazine.
cell enables the panel to put out charging voltage even if most of it is in the shade. (if the panel has been made for it) I’ve put in a few dozen solar power systems in remote locations (i was a Radio tower ground tech) and a few boats, it does have a good performance improvement if there is something around to cast shade on the panel. Since doped panels mostly have them built in, it’s a no brainier in my book for marine usage. Almost on any panel not made for it, if there is as little as one cell shaded, it will cause a severe drop in power. BTW, im certified in solar power installations (but not wind, but ive done them too). Also a highly recommended reading resource is Home Power Magazine.
Confusing/Misleading Thread
Ken. I recommend you provide us your electrical loads, how many hours per sail you will be using them and how many times per week you will be sailing. Just tell us nav lights, radios, etc and we can make a rough guess. Also include any electrical loads you will have on when away from the boat. Don't be pessimistic with the loads. Be realistic. Also I recommend that you read the following posts:1,2,3,4 and 11. Disregard the rest.
Ken. I recommend you provide us your electrical loads, how many hours per sail you will be using them and how many times per week you will be sailing. Just tell us nav lights, radios, etc and we can make a rough guess. Also include any electrical loads you will have on when away from the boat. Don't be pessimistic with the loads. Be realistic. Also I recommend that you read the following posts:1,2,3,4 and 11. Disregard the rest.
The AIR-X normaly dosnt meet peak
output in most areas. I tend to calculate it as a 100 watt power source when im doing averaged calculations. But, it is cheap in comparison to many other turbines I have seen for marine use, and it can put out the 400 watts if you are in a windy area, plus, add in the integrated charge & speed controller, I like to use it for the KISS factor.
output in most areas. I tend to calculate it as a 100 watt power source when im doing averaged calculations. But, it is cheap in comparison to many other turbines I have seen for marine use, and it can put out the 400 watts if you are in a windy area, plus, add in the integrated charge & speed controller, I like to use it for the KISS factor.
Diodes
In general there are six solar cells in a series which will deliver about 20V open circuit. That is why solar panels usually have multiples of six solar cells, i.e. 6,12,18, etc. When the panel is delivering 15V there are six cells delivering 2.5V each. You only need one diode per series string. Putting in the other five diodes is redundant and will actually hurt. The diode will cause a drop of about .5 to 1V per diode. If you have six diodes in the string, you will lose from 3 to 6V in the string rather than .5 to 1V with a single diode. If one cell in a string is shaded and is not delivering any voltage, it will not subtract from the string voltage. It just does not contribute. That cell just becomes a conductor. Unless of course, each cell is delivering the full 15V. In that event disregard this post.
In general there are six solar cells in a series which will deliver about 20V open circuit. That is why solar panels usually have multiples of six solar cells, i.e. 6,12,18, etc. When the panel is delivering 15V there are six cells delivering 2.5V each. You only need one diode per series string. Putting in the other five diodes is redundant and will actually hurt. The diode will cause a drop of about .5 to 1V per diode. If you have six diodes in the string, you will lose from 3 to 6V in the string rather than .5 to 1V with a single diode. If one cell in a string is shaded and is not delivering any voltage, it will not subtract from the string voltage. It just does not contribute. That cell just becomes a conductor. Unless of course, each cell is delivering the full 15V. In that event disregard this post.
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