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Solar Power in the Third World
KTS writes: "Over at Wired, there's an interesting article about the use of solar energy by the rural poor in the Dominican Republic. Soluz, Inc., a Massachussetts-based company, has installed thousands of solar panels on an island where most of the rural population is cutoff from the power-grid. Says the article: "Rural communities rely on solar energy for everything from pumping clean water from aquifers to recharging cell phone batteries." According to another article, the Dominican Republic now has "more [solar panels] per capita than anywhere else in the world." After constantly hearing about the misuse of technology, stories like this make you feel good. With solar power, it looks like developing countries can avoid much of the downside that comes with electric power, while reaping the benefits. Zero polution, no overhead lines, and no squandered petroleum (after all, we need the oil for ourselves)."
The thing that really makes solar better for them than anything else is that you can have your own solar panels, and the power doesn't have to be sent anywhere. That means that you don't rely on power lines which may go unmaintained or a power plant which may go offline. The first-world power grids work well because there's a lot of redundancy and utilities which can maintain the power lines.
If you don't have thousands of other paying customers on the same segment as you, you're not going to get great service, and you'd do better to just do it yourself with a solar system or a generator, and solar's just easier at that scale.
Danny.
I have written over 900 book reviews
Fuel cells are not in competition with solar energy, because fuel cells are not an energy source. They are a method for storing energy (like batteries, but better). You still have to generate that energy somehow (and solar is as good a method as any)
I don't care if it's 90,000 hectares. That lake was not my doing.
Third world countries usually don't have the pollution problems that others do
Obviously, you've never been to a city in a third world country. They most definately do have pollution problems: pollution control on cars is far less, heating and light are often generated by burning kerosene, coal, or even animal dung, and forget about sewers and garbage collection. Pollution controls for industry are much less strict if enforced at all. Plus the density of people is usually higher.
It's extremely difficult to do a complete audit of the environmental impact of any technology. There is definitely a "tip of the iceberg" effect at work. For example for every pound of household trash, several pounds of trash were created before the materials ever reached the house. This effect is very pronounced in the case of PV, but it exists for alternatives such as fossil or biomass fuels as well. You have to do a a rigorous audit of EVERY alternative.
Another important factor is scale. You cannot compare the environmental impact of, say, a wool coat with a polypropylene fleece one, without taking into account the scale of production. To produce a single coat, the cost of the polypro coat is vastly greater, but the marginal effect for each new coat is less, whereas the environmental impact of wool increases at least linearly and possibly faster at very high scales of production. At some point, the marginal impact of the next wool coat may meet or exceed the polypro.
Perhaps an alternative to complicated environmental auditing is simply to internalize the costs of pollution by regulating disposal of wastes and charging a fair price to cart what can be disposed of "away". If the PV cells are indeed manufactered in Massachusetts, then the cells are manufactured under some of the strictest environmental regulation and enforcement in the world. Very likely the environmental costs of PV cells are much more fully accounted for in their price than the costs of fossil fuels.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
I was there in February (great place,except Puerta Plata) and there were constant blackouts. Most hotels and restaraunts had backup generators to provide power. The main power plants were diesel barges in the harbor. In the countryside I rarely came accross power at all unless it was by a generator...actually I went to a few places that didn't which adds quite a bit of time to your day. I didn't notice any solar power. But I'm happy to hear that they are attempting to use it. A very good way to get out of poverty is to have the extra time given by available power and sewage systems. I estimated that lack of these things added about 3 hours of work to an average person's day just to keep clean and prepare food. Time that could be much better spent at other educational or profitable endeavors. If anyone goes there. Go to the k-ramba bar on Calle Isabella in Santo Domingo. The energy engineers hang out there and it is a very good bar.
Third world?! You mean the place you can't place a call to because the locals tear down the COPPER wire to sell? That's where you're putting in solar panels that cost more than a person can earn in 5 years?
They'll be gone by the end of the week.
Democrats or Republicans. They are both taking us to the same place and they are not afraid of us anymore.
anyone know the lifecycle cost of solar cell power vs other types of power?
:-)
Sorry, I forgot to answer the second part of your question
Let's assume that this 40 watt system will operate at 12 hours a day, and let's derate the output to 40 watts over 8 hours (instead of 12). That gives us 320 watt hours per day of work, or 115 kilowatt hours per 360 sunny days. You will have to reduce that figure depending on the local climate.
Where I live, electricity costs about 9.5 cents per kilowatt hour, so this setup would be worth about $11 per year. Not much of a bargain - for me anyway. (In case you are wondering, I probably get 350 days of full sunshine per year.)
But I don't think MY cost comparison is of any interest to the people in the article. The first few hundred watts are probably the most productive anyway. After that, the watts are probably just "wasted" on entertainment.
A dingo ate my sig...
The best solar cells generally have about 30% efficiency, relative to the total flux of sunlight hitting the earth in the given area. To output 100 MW requires about 1 square mile of cells
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Interesting maths there.
You get ~1kW/m^2 of sunlight, so that's 2560000kW of raw sunlight, which at 30% efficiency is:
2560000kW * 0.3 = 768 000kW == 768MW
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Point of view from an applied physicist:
Sunlight from the earth is 1.2 kW/m^2 (higher than your estimate). However, 30% efficiency is a pretty big overestimate of how much you can get from a presently economical solar cell. There are solar cells approaching 30%, but these tend to be made out of more exotic materials and are not as easily manufactured.
Starting from an incident flux of 1.2 kW/m2:
Half the time it is night. So averaged over a day gives: 600 W/m2.
But in most places, not every day is sunny. So, hack another half off that: 300 W/m2.
Also, the efficiency of a solar cell is strongly dependent on the angle of incidence of the sunlight. Assuming a low cost installation where the cells aren't pivoting (expensive and prone to break down) to catch the rays gives a loss in available flux. Using a generous a cos^2 depenenced takes us down to: 150 W/m2
(Note: It is probably much worse as the cos^2 only accounts for effective reduction in solar cell cross-section area as the sun rises and sets. For grazing incidence light most of the sunlight will reflect off the solar cell. And yes, exotic solar cells have been designed to reduce this, but this adds to cost and manufacturing difficulty.)
Now, apply a realistic 20% solar cell efficiency: 30 W/m2.
Thus, a typical solar cell can be expected to yield on average (a generous estimate):
30 W/m2.
Of course, this ignores the efficiency of any storage system you might have if you want to make use of the power generated when the sun is not directly overhead on a clear day. So to try to get a more realistic feel, hack off another half to account for efficiency and grazing reflection:
15 W/m2.
So, a square mile array of solar cells could make an average contribution of:
1600 m * 1600 m * 15 W/m2= 38,400,000 W
This is one-twenth the value of the previous poster and a bit closer to the original post, but 38.4 MW can power a fair number of homes.
However, as the previous poster pointed out, in most cities, you could get more bang for your real-estate via other means.
However, when the sun is directly overhead, on a sunny day, you will get a peak performance of roughly 240 W/m2.
Since this is the time when power is most needed anyways, this points to solar cells being used to offset peak power demand when everybody's air conditioning kicks on simultaneously. I don't expect solar cells to be the primary source of power anytime soon except in special situations.
Kevin
Several semesters ago in one of my college classes, my profesor told us about his research. He goes to guatemala(where I'm from), to install solar stoves. They are very simple, but they work very good. It decreases their need for firewood. Any way, here is the link to the article. It was posted in the University's magazine.
And what's more, in 'developed' countries, we've already made a huge investment in power stations to supply our mains electricity, plus systems to distribute that power.
So one important comparison has to be that between spending, say $10,000 for a solar facility for a village (still a lot of money in most places on the planet), and $several_million to build gas/coal/nuclear/whatever powered centralised power stations and distribution networks. Which might end up more economical when calculated across an entire country, but has to be done in one fell swoop rather than being achievable piecemeal, village by village, region by region.
And then there's the ongoing cost of fuel, the carbon release or nuclear waste disposal, the moving parts, the high operating costs...
It will cost us a lot of money to convert to solar in the short term, but, as Keynes so nicely put it, in the long term, we're all dead. and it's in the long term that our grandchildren will thank us for having the foresight and wisdom to take a hit today and set the change in motion.
TomV
I live in a third-world economy, and the air here in California is pretty clean.
Comment removed based on user account deletion
You could always try a flywheel.
"Patriotism is your conviction that this country is superior to all other countries because you were born in it." -- GBS
Unless the technology can be maintained with local expertise it is just putting the people in a dependant relationship on more industrialized nations. There is a path that technological development has to go on to empower the people, and sometimes that means that less good technologies have to be used.
Even Slashdot wants to hide some things
First off, the electric situation is terrible in that country. This is not just for the remote undeveloped rural regions. In the major metropolitan areas, even the capital city, Santo Domingo, just about everyone who can afford it has their own gas generator. Why? Because the power outages are frequent and of great duration. In the US, if the power goes out frequently, anywhere, (say like California recently) it makes front page news, people are crying out because "We were out of power for 4 HOURS last night!" In DR there are parts of the city where they measure the time the power is ON like that, not where it is off. It's more like "Woo Hoo, we had a full 6 hours of power today!" The solution to this problem for many is gas generators. But these are really expensive to purchase, so it's the middle to upper class (who are vastly outnumbered by the lower class) that are able to buy them. These generators are also very expensive to operate, since gas isn't exactly cheap in the third world (like it is here, he says sarcastically) so most people can't have them or even operate them.
I believe the idea of solar panels to be a blessing for the country. Goodness knows that the government is corrupt, and the ruling class doesn't give a shit about the poor. It's a lack of will and cash that is preventing the outskirts from even being wired, and it's corruption that causes the places that ARE wired to remain dark. Solar panels are a way for the people to power themselves, cheaply. This has to be good.
anyone know the lifecycle cost of solar cell power vs other types of power?
--
Scientists restrict study to entire physical universe; creationist
This is one of those ideas that makes such perfect sense. Solar is currently an expensive solution on a per KWh basis to add to an existing grid. But, when there is no power infrastructure in place, it's not surprising to see it as a good solution. I'm glad there are people finally out there trying to get it going.
The big trick with a low input power system like that is the user's energy budget. Here in the states, we're used to having a huge budget for power. But, when you live on battery or generator power, you learn to economize. Folks in rural areas won't have the energy budget we may be used to in an urban area, but any power is better than none, and Solar is often a great solution. One reason many long distance cruisers (sailboats) rely heavily on big batteries and a rack of solar cells...
Never attribute to malice what can as easily be the result of incompetence...
Not only that, but youre using a NUCLEAR power source! Not many of you may know this, but the sun is a giant NUCLEAR furnace, where hydrogen is built into helium, at a temperature of MILLIONS of degrees. Were you also aware that most solar panels actually collect the RADIATION put out by the sun? I dont know about you, but I dont want RADIATION collectors anywhere near me or my CHILDREN. We need to stop all use of NUCLEAR power, including solar, and move to safe, clean COAL energy, just like our VP says to.
Only in America can the above statement be Funny :-(
Never underestimate the dark side of the Source
What I learned, however, was that the sun is much better at heating things up than creating electricity. Heat a home, or water for a home, or a greenhouse - at these the sun excels. Also, we're still not very good at converting that energy into electricity. We would have been much farther along 'cept for fucking Ronald Reagan (link's dated, but funny). Bastard killed off solar energy research in the 80s.
Anyway. Solar power is useful, yes, especially in 3rd-world countries where people aren't such energy hogs. But until our technology improves vastly (or we all start using much less energy), solar-generated electricity isn't going to help the 1st world very much.
"We all say so, so it must be true!"
This isn't as much "normalization" as it is "don't take so many drugs when you're designing tables."
It seems to me that I don't use much of my roof space. I mean, I can't even get up there to bask in the sun or get drunk and fall off for the neighbors' amusement. Think there might be a square mile of south-facing roof in your town?
He has many hundreds of usenet posts, ideas about converting an existing house to 100% solar, low cost and warm homeless shelters, and is conducting solar heating experiments, all using inexpensive / easily obtainable materials.
If you're interested in solar heating, you should check him out.
The Department of Energy does actually have a few programs set up in the United States to promote solar power use in the US. One is the Million Solar Roofs Initiative (MSR) which provides grants to state and local partnerships to try develop uses for solar energy in communities. The program plans to have a million solar roof systems in place in the United States by the year 2010.
There is a map of current locations of partnerships in the United States here:
http://www.eren.doe.gov/millionroofs/tally.html
The main webpage for the program can be found here:
http://www.eren.doe.gov/millionroofs/"
And here is a list of projects that have already been put into place in the United States related to this program:
http://www.eren.doe.gov/millionroofs/news.html
bbh
While this may sound crazy, flourescent lights have come a long way and the technology is fairly common and is becoming cheaper everyday.
The cool thing about flourescent bulbs is that they now come in standard "edison" screw type sizes so you don't need to buy those long tubes. On top of this, they are over 80% efficient (only 20% of energy is turned to heat) and last 10,000 hours! [5 - 7 years under average use] Good old incandescent bulbs only last 1,000 hours at most and are only 15% efficient. (85% of the energy goes up as heat.)
Not only is this a boon for 3rd world countries, but it is helpful for 1st world ones with states that have rolling black-outs. :^)
So if you're a Californian trying to get in on the 20/20 deal, you might want to look into getting flourescent lights for your house. Not only do they produce less heat, they consume only 1/5th the electricity.
The best place that I've found to buy flourescent bulbs online is some company called http://www.energyguide.com and New Englanders get a $5 discount per bulb making them practically free. So what are you waiting for? Save yourself some money by lowering your electricity bill! (and perhaps avoid rolling blackouts!)
Living here in California where people are constantly complaining about rising electric rates and rolling blackouts that disrupt your soap opera viewing, articles like this really help put things in perspective. Imagine a country where renting a 40-watt photovoltaic panel can be a life changing experience. Totally alien to our own way of life.
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"From each according to his abilities, to each according to his needs" -- T. Jefferson
If the government really cared about getting alternative energy in use here in the US, they'd enforce net metering laws. What this means is: you hook up your [wind|solar|thermonuclear] electrical source to the grid, and when you put electricity back into the grid you get credit for it. Simple enough. With older technology, all that was required was a device to make sure that your current was in phase with the grid, and your meter would run 'backwards'. Now with the new, electronic meters, doing so would make you PAY for the electricity you put into the grid! This is absurd. In many states there are LAWS that REQUIRE the utilities to implement net metering, but they are being blatantly ignored. If you want more info, read Home Power Magazine, which has really good info, all in an archive for FREE! (but hey, subscribe, send them some money, it's a worthy cause).
It takes hard-core chemical usage to
manufacture photovoltaic cells. Just remember
that there are other ways to exploit the sun,
as well (solar ovens, solar heating ranges,
et cetera).
The economics of solar power are actually excellent. A few pertinent facts:
1.) Solar cell sales have grown at a CAGR over 15% for the last 15 years. PV production has been running at capacity for over 10 years, despite construction of new PV manufacturing facilities. PV sales are on allocation and have multi-year backlogs.
2.) PV sales are now far more dominated by considerations of cost effective power generation than by considerations of cost effective publicity generation.
3.) US installations of solar cells are very widespread, but are now being installed mostly by people who do not spend money on publicity regarding the installations.
4.) Most installations are cost justified by the cost of installing grid power vs the cost of installing the PV system. For a small data monitoring system (commonly needed for railroads, natural resource sites, etc.) the cost of the PV system is usually less than the cost of installing one utility pole. So you see PV power even in fairly urban areas. For larger installations, the construction cost tradeoff is usually something like 1-2 miles from power line to power need. Then PV makes sense. There are lots of sites like these, but they are all miles from the nearest road and get little publicity.
The question of solar power is not whether it is useful or not, or clean or not. It's really a matter of whether it's economical or not.
In the Dominican Republic, a small island isolated from the immense power grids of places like the USA and Europe, with limited ability and resources to produce its own power, it's perfectly feasible (even with the high cost of replacing solar panels in the long run). However, we have a huge infrastructure for pumping, transporting, and burning petroleum.
High efficiency, low-maintenance solar cells are a good direction in which to spend research $$, but I think it'll take a major shift in economics to make this work--especially with competing fuel sources like fuel cells on the very-near horizon.
The best solar cells generally have about 30% efficiency, relative to the total flux of sunlight hitting the earth in the given area. To output 100 MW requires about 1 square mile of cells - that's enough power for about 18,000 people (Americans, that is... or about a million Dominicans).