Advtantages & Disadvantages of Solar & Wind Energy

Ok so I was hoping we can put together some pros/cons of the most popular alternative energies…

I’ll go first:

Solar

Pros: Clean, Easy to implement,
Cons: Battery Store for night use, do they degrade over time,

Wind:

Pros: Night or Day Power, countries are adopting the technology fast
Cons: some regions aren’t windy, the bird factor, noise level?

How about tidal energy? I don’t know much about it, but would be interested in hearing what others know. Seems to me that this is a HUGE source of energy that we haven’t even begun to tap. And it’s clean. I guess the cons would be the structures that need to be under the water … but if we put them in the right place, seems a small price to pay.

What would the environmental concerns be over tidal power? How much damage would it cause to build something like that? What would the long term effects be on the aquatic life around the thing?

Lot’s of questions to ask about this one.

What would the environmental concerns be over tidal power? How much damage would it cause to build something like that? What would the long term effects be on the aquatic life around the thing?

Lot’s of questions to ask about this one.

For all this investment, the average electric power output is severely limited by the twice-daily ebb and flow of tides: average output of tidal electricity is less than 40% of the installed generating capacity; production of power from river dams typically averages 70-100% of installed capacity. Finally, the lunar cycle of 24 hours 50 minutes means the raw production of tidal energy moves in and out of phase with the normal, solar-oriented daily pattern of electrical consumption. Unlike the energy from river dams, the daily, monthly and annual availability of tidal energy is fully predictable, but it must be either stored or integrated with other sources of generation that can be adjusted to accommodate the fluctuations of tidal generation. There are relatively few coastal locations in the world where the tidal range (ie, the difference between high and low tides) is large enough to justify exploitation of the available tidal energy. Not only must there exist a sufficiently high tidal range (at least 5 m) for construction of an economically feasible plant, but the site should also include a natural bay which can store a large volume of seawater at high tide and be so situated within the estuary that the operation of the plant will not significantly change the tidal resonant system (see link).

link

Raptor, just wanted to add a pro to your wind power. I know many might not share this view, but I have driven by a couple of places where there a ton of the wind towers. I have to admit that it was actually an awesome sight, and I would almost consider it art.

I like the idea of wind power. I wonder if anyone has tried to grow food crops along in between the turbines?

First, I would separate solar electric from solar thermal.

Since most (if not all) states require buy back deals from the utility, battery banks are only used for off-the-grid applications. You sell extra electricity to the utility during the day and buy it at night. This is called grid tied.

I would list expense (about the same as coal generated) as a drawback of photovoltaic power along with a world wide shortage of PV panels the last year.

As far as solar thermal, lots of upside. It produces about six times the power per square foot as photovoltaic. The hot water panels cost less than half as much per square foot, too. Solar thermal pays for itself in 5-10 years and lasts at least 30 years.

As far as a downside, copper used in the absorber plates and pipes is through the roof. But its kind of like oil: a doubling of oil prices only marginally raises the price of gas since the raw material is only one expense. Manufacture and distribution of solar panels does not rise as quickly as the copper, thank god.

I could go on forever about solar thermal. It is the best idea no one knows about, as evedenced by your omission. Thanks for the forum.

I like the idea of wind power. I wonder if anyone has tried to grow food crops along in between the turbines?

Absolutely. There is a wind farm out in Southwest Kansas that I am familiar with. It was farm land before the wind farm and it continues to be farmland now.

Has anyone installed, and is currently using solar panels to heat and generate electricity for their home?

Thanks, stuboyle–I’m glad to hear that someone’s doing that!

First, I would separate solar electric from solar thermal.

…

As far as a downside, copper used in the absorber plates and pipes is through the roof. But its kind of like oil: a doubling of oil prices only marginally raises the price of gas since the raw material is only one expense. Manufacture and distribution of solar panels does not rise as quickly as the copper, thank god.

Another downside to solar thermal is that, for domestic uses, you need to use the heat energy when it is available, or before it goes away. I.E. a homeowner who installs solar water heating wouldn’t get much benefit if he takes his shower every day at midnight (unless the storage tank was extremely well insulated).

Larger applications, like solar towers can get around this by heating molten salt instead of water ([URL]http://thefraserdomain.typepad.com/energy/2005/09/aabout_solar_to.html>link)

As far as wind energy is concerned, this company is developing a novel idea for chasing the wind down at sea and storing the energy as hydrogen gas.

link

Back to solar thermal, my 200 gallon solar storage tank gets up to 170 degrees this time of year and stays above 120 for two days of clouds (even when we’re using hot water normally). Solar heat is usually not sized for 100% of your use. You need a backup. That could be considered a downside. But tanks do not cool down that quickly. Even when insulation is so-so.

Heat storage for homes is on a different scale if done right. Houses built on 2 foot sand beds have 100 times more storage than my 200 gallon tank and do well in the MN climate. Its tough to size the solar to the sand bed, though, but “good fits” provide 90% of your heating if you’re willing to live with 60 degrees during a cold snap.

Back to solar thermal, my 200 gallon solar storage tank gets up to 170 degrees this time of year and stays above 120 for two days of clouds (even when we’re using hot water normally).

Wow. what are the details on your system?