Solar Power - Ways of Producing Electricty from Sun

 

The solar radiation reaching earth from sun can be converted to electricity which provides a clean, renewable and free source of energy to us. The solar power systems are in developing stage (there are some commercial usages but most methods are in prototype stage due to high costs avoiding commercial use). Ways of producing electricity from sun energy can be gathered under two major headlines. Photovoltaic (converting the solar power directly to electricity) and Concentrated Solar Power (CSP - which is roughly concentrating the sun beams thus creating a high temperature and converting heat energy to electricity by known methods).

Photovoltaics

Photovoltaics is the technology used for directly converting the sun energy to DC electricity. You are already familiar with photovoltaics if you've ever used a calculator. Usage of photovoltaic cells in calculators is a good idea to get rid of batteries but you can't extend the usage to higher power needs because of high costs of photovoltaic cells. The power efficiency of photovoltaic cells are between 12-24% which is considered low compared to the other energy sources. The high cost of photovoltaics prevent them from wide usage but they have many usage areas like satellites which need continuous power without batteries or small devices (calculators, watches).

Concentrated Solar Power (CSP)

Concentrated Solar Power systems concentrate the sun beams to produce heat and then convert the heat energy to electricity by conventional ways. There are several designs for concentrating the sun beams but the method is the same in all designs. There is a reflector which concentrates the beams in a heat collector (also called absorber or receiver). There is a fluid (molten salt for example) flowing in the receiver and stores heat. The hot fluid flows to a heat engine and the heat energy is converted to electricty. There are several designs which differ in the way of concentrating sun beams and storing heat.

Parabolic Through Design

In Parabolic design there are parabolic mirrors collecting the heat on the receiver which is placed on the mirrors focus. The energy production is as explained above. The hot fluid is flown through pipes and transferred to the heat engine. This is the most known and practiced method of solar power plants and there are several power plants full operational. Parabolic Through power plants have an efficiency of %20 but less area usage and cheaper design is an advantage compared to other systems.

Power Tower Design

The Power Tower Design is similar to the parabolic design but there are many number of flat, mobile mirrors (also called heliostats) which focus the beams on a single receiver (tower) and all energy focused on a single point is creating higher temperatures and thus creating energy with higher efficiencies. There are several number of power tower plants in production. Although parabolic through design is proven, the higher efficiencies and lower energy cost predictions are creating more investments for Power Tower Plants.

Dish Design

Dish Design uses the same principle with the satellite receivers. The dish collects and focuses the energy at a receiver facing the dish. There are several advantages of dish design, the efficiency is high (the efficiency up to 40%) like in tower design and each unit has it's own stand alone structure which is making it fit for smaller applications (unlike tower design which has a high central tower cost.) The dish design has a high cost when compared to other system because of its complex design and requires more maintenance. However high efficiency is promising a future for dish designs also.

Fresnel Reflectors Design

Fresnel Reflectors is a new concept similar to parabolic through design. The fresnel reflector design uses a set of flat mirrors which share a common receiver. (Unlike parabolic design which each mirror has its own mirror.) The advantage of fresnel reflectors is the usage of flat mirrors, less number of receivers and lower area/energy ratio are decreasing the costs dramatically. Although efficiency is lower than parabolic through design low cost per energy can make fresnel reflectors used widely in the future. The fresnel reflectors are in developing stage yet.

More by this Author


Comments 18 comments

raymondphilippe profile image

raymondphilippe 8 years ago from The Netherlands

That would take care of CO2 too.

Can't wait to see a few of them over here. Plus some additional sunshine. :-)


Zsuzsy Bee profile image

Zsuzsy Bee 8 years ago from Ontario/Canada

This has to be whats in our future. Between Solar power and Wind power, clean fuel a-plenty.

Great HUB regards Zsuzsy


bloggerdollar profile image

bloggerdollar 8 years ago Author

Thank you for your comments. I hope goverments encourage industries to invest more in green energy.


chabrenas profile image

chabrenas 8 years ago from middle of France

Several countries (France & Germany, for a start) will buy excess power from private wind & solar generators, and there are significant grants available, too.

Although only 0.04% of the world's energy is currently supplied by solar systems, there are applications where it would be stupid not to use them. e.g. at remote sites in sunny climates, and for water desalination plants. Things can only get better.


bloggerdollar profile image

bloggerdollar 8 years ago Author

The serious entrance of solar power systems will be when they are commercially advantegous. The reports are predicting that those systems will produce cheaper energy then fossil fuels in 8 years or so.


greathub profile image

greathub 8 years ago from Earth

Hi

Its a nice article. I have presented a simple method to design and fabricate a dish reflector (solar concentrator) in my hub:

http://hubpages.com/education/solar-reflector

Would you like to visit and give comments?


RetroReviewer profile image

RetroReviewer 8 years ago from Metro Philly

You've ignored Solar Power Satellites, the REAL long-term solution to our energy situation. Read up on Wikipedia http://en.wikipedia.org/wiki/Solar_power_satellite


Ghost32 8 years ago

I've learned a good bit from this Hub. On the other hand, I read (about a year ago) about a method termed "conductive solar". This involved sort of halfpipe-looking collector "troughs" set close to the ground. Instead of collecting the LIGHT from the sun, this method purported to collect HEAT directly (from the sun). But I haven't been able to locate a single additional bit of info on this technology since, or even remember where I saw the original article (though I THINK it might have been in a Mother Earth issue).

Anyone else know about this?


bloggerdollar profile image

bloggerdollar 8 years ago Author

Hey Ghost Thanks for the comment.

All the methods listed under the CSP - Parabolic, dish system are producing energy from heat. The system concentrates the solar heat and the heated fluid is run through a pipe to a heat-energy converter.


Jensen Boire 8 years ago

For those interested in investing in solar energy companies although somewhat different from the ones mentioned above, feel free to post on my website.


mike 8 years ago

Look i am reading about all these great ideas!And i live in Arkansas!The thing is we have places here an al over the world that could harnes the power from like geo thermal guizers that already exsists for very little cost why doesnt the goverment do these things?


chi4505 8 years ago

Solar Power and wind power are definately the way of the future.

http://howmakeelectricity.blinkweb.com/index.html


vansh 8 years ago

great idea


F!~~WaVeZ~~F! 7 years ago

Wow i n3v3r kne thIs stuff b4...but its r3al h3lpfu1...thnkxx 4 makin this w3bsite.


Kahng Ho Choi 7 years ago

I wish to introduce your Parablic dish or trough solar generating system

into Korean market.

Please linform your mail address, to which I will send the detailed inquiry.


bharathi 7 years ago

it would be bettet having a brief aboutparabola and its applications


adair_francesca 5 years ago

Nice hub! I learned from all the information you stated. Solar power is very promising and a great alternative especially these days conventional electric supplies costs higher.


Akliliu 5 years ago

THANK YOU FOR GIVING ME GREAT KNOWLEDGE ON SOLAR ENERGY.

How can I practice this?

Would you help me to practice Parabolic Through Design

Aklilu from Ethiopia

    Sign in or sign up and post using a HubPages Network account.

    0 of 8192 characters used
    Post Comment

    No HTML is allowed in comments, but URLs will be hyperlinked. Comments are not for promoting your articles or other sites.


    Click to Rate This Article
    working