Small-Scale Solar Thermal Capacity Is Equivalent to 245 Nuclear Plants

October 6th, 2012 by Nicholas Brown

When solar thermal heat collection systems are factored in, total global solar energy capacity is a whopping 245 GW (2011), which exceeds that of wind energy (not by far, though), which is 238 GW (2011). Photovoltaic solar (these are the solar panels most people are accustomed to) capacity is a small fraction of that total solar amount. Photovoltaic is only 50 GW, while solar thermal accounts for the other 195 GW.

You have probably heard people argue about the fact that solar panels have a much lower power-to-size ratio than nuclear power plants, which can generate plenty of power with even one pellet of uranium.

Here is a more relevant argument: due to the fact that solar panels are the only generators that can be integrated into every shirt, knapsack, laptop, tablet, phone, roof, window, door, curtain, wall, car body, binder, watch, bridge, driveway, and even sidewalks; they can be set up to waste the least amount of land, even compared to nuclear power plants, which require the virtually permanent burial of toxic waste and can’t exactly be built on houses, carports, bags, etc.

This goes to show the paramount importance of how technologies are applied. Application is everything! (Not literally.)

There are two main solar thermal systems in use today:

1) Solar thermal power plants that generate electricity through the use of sunlight to boil water or mineral oil and produce steam, which then drives a steam turbine.

2) Solar thermal collectors that collect heat from sunlight and directly use it to heat water for showering, laundry, dishwashing, etc.

Middlebury College’s Solar Array.

Both the solar and wind industries have exhibited strong growth for years, and according to an IEA (International Energy Agency) roadmap, solar could account for one-sixth of the world’s low-temperature heating and cooling needs by 2050.

Paolo Frankl, Head of IEA’s Renewable Energy Division, said: “Given that global energy demand for heat represents almost half of the world’s final energy use — more than the combined global demand for electricity and transport — solar heat can make a significant contribution in both tackling climate change and strengthening energy security.”

The IEA’s Solar Heating and Cooling Roadmap outlines how best to advance the global uptake of solar heating and cooling (SHC) technologies, which, it notes, involve very low levels of greenhouse-gas emissions. Some SHC technologies, such as domestic hot water heaters, are already widely in use in some countries, but others, like large-scale solar fired district heating, are just entering the wider deployment phase, while solar-powered cooling is still at the development stage.

The IEA roadmap also pointed out that there are industries which require large amounts of heat for their manufacturing processes, which could utilize solar thermal heat directly.

Source: Environmental Research Letters
Photo Credit: Stefano Paltera/U.S. Department of Energy Solar Decathlon

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Tags: CSP, global combined solar energy capacity, global solar capacity, global solar capacity including heating, global solar energy capacity, solar thermal panels

About the Author

Nicholas Brown writes on CleanTechnica, Gas2, Kleef&Co, and Green Building Elements. He has a keen interest in physics-intensive topics such as electricity generation, refrigeration and air conditioning technology, energy storage, and geography. His website is: Kompulsa.com.

GeorgeS

Good article. Solar thermal is more efficient than solar PV and cheaper. It is good for residential but the commercial space is untapped especially in the hotel and laundry industries.
http://www.facebook.com/GreenSpiralDragon Jamie Clemons

And they don’t melt down leaving hundreds of square miles uninhabitable.
Madan Rajan

While we can celebrate the growth of Solar Thermal, we cannot compare it with Nuclear which runs @ 85% efficiency.

Opposition to Nuclear has helped the Coal become a bigger source. Last year, I believe Coal consumption was 3,800 MTOE which brings it pretty close to Oil Consumption, besides more heavy dirty crude is becoming more common.

If you guys believe that Global Warming is hoax. Go ahead and mock at Nuclear.
- Bob_Wallace
  
  Obviously we can compare thermal solar with nuclear. We can compare based on cost, safety, ease to site, and time to install.
  
  I don’t know what country you’re talking about with your coal numbers but coal use has been falling in the US. Coal provided 44.8% of our electricity in 2010, 42.4% in 2011, and fell below 35% in the first half of 2012.
  
  We use almost no oil for electricity production in the US. Less than half a percent of our electricity comes from oil Most of the oil is used in Hawaii (which is rapidly installing renewables) and a few remote settings in places like Alaska.
  
  I don’t think any of us even start to believe that global warming is a hoax. We do largely understand that nuclear is too expensive and too slow to install to be considered a part of the 21st Century grid.
- jack miles
  
  Nuclear is toast! We don´t need it or want it. To dangerous, too dirty, too expensive. If all homes had solar heaters installed we could do away with all nuclear and coal. It is not smart to produce electricity (specially dirty plants) and send it many miles to homes so it can be “wasted” in a glorified short circuit to heat water.
  
  By the way a solar thermal panel has efficiencies over 85%.
fsc

For a long
time I have wondered why solar heating is the ugly stepsister of sexy
photovoltaic. I have heated the water in my home and replaced natural gas
burning for two years. I am one year away from payback. You will be pressed to
get payback in 10 years with other technologies.

It is true
that solar heat will not make you 100% off-grid; but if you are considering putting
10 panels on your roof then consider a combined system of 8 photovoltaics and
two for hot water. Run the numbers and you will see the difference. If you are
considering starting small and building up, start with hot water. You get more
bang for your buck.

Nicholas:
Low grade means that unless you use expensive mirroring and tracking, the water
will not get hot enough to, say, run a metal smelter or a steam turbine. But you are right. For home use “low grade” is
definitely high enough. I had to use an isothermic mixing valve because the
water was coming out too hot for showers; and I have no intention of skinning a
chicken in my kitchen but that is how hot it was without the valve.
- http://www.facebook.com/matthew.t.peffly Matthew Todd Peffly
  
  Two big thumbs up “fsc” you nailed it.
Bill_Woods

“Photovoltaic is only 50 GW, while solar thermal accounts for the other 188 GW.”

The way I read it, PV is not included, nor CSP for electricity.

… by contrast, the perhaps less glamorous but at present far cheaper
technology of solar thermal heat collection is well ahead. …
By 2010 there was 195GW (th) installed global (118GW of it in China),
rising to 245 GW by 2011.

But as Anne said, electricity and low-grade heat are not directly comparable. If used to drive heat pumps, 1 GW of electricity can produce 3-5 GW of domestic heat.
- Nicholas
  
  Yes, but that isn’t what it is being used for most of the time. Thank you for the reverse-cycle heat pump suggestion, though.
  - Bill_Woods
    
    … and ‘188 GW’ isn’t anything — you subtracted 50 GW of PV from 238 GW of wind.
JMin2020

Small scale solar thermal may not compete with and replace Nuclear Power; but large scale CSP applied to molten carbonate storage systems may well do so.
globi

Nuclear power plants can also not be placed on existing roofs nor can roofs provide them with enough cooling water. In addition, uranium mining requires far more area than the nuclear plant itself.
http://www.facebook.com/matthew.t.peffly Matthew Todd Peffly

Anne, I agree with you on the headline. But while you might not like low grade heat. For many applications it is perfect. And if I get it from my roof or heat it with gas or electric, it really is no different. I get hot water which is what I wanted.
- Nicholas
  
  I don’t understand why it is called “low-grade heat”. It is by far the most efficient way to obtain heat from solar, because most of it is not wasted.
  
  Almost all of it can be captured, and it is directly used to heat instead of being converted from electricity (which is inefficient).
  
  It shouldn’t be called low-grade.
Anne

“Small-Scale Solar Thermal Capacity Is Equivalent to 245 Nuclear Plants”

I find that title to be misleading.

It ignores capacity factor. 245 GW of solar (at 15% capacity factor) is equivalent to less than 50 GW of nuclear (at 75% capacity factor).

And there is more. You can not compare low grade heat (solar thermal) GW’s to high value electric GW’s (from PV, wind or nuclear). This exact same thing is done by the fossil fuel interests to downplay the role of renewables. Don’t fall into the same trap.
- rkt9
  
  Anne, brilliant comment, I feel you are a critical thinker.
  The message I got from this article, is that when we quantify solar energy, we often neglect factoring in the simple thermal energy factor that is currently being utilized from things like solar hot water for pools, showers etc.
  If you have the time, (or any others that frequent this site) I would be interested in your thoughts on this recent article I read.
  http://newenergyandfuel.com/http:/newenergyandfuel/com/2012/10/04/choosing-to-spend-billions-or-make-trillions/
- Luke
  
  Technically, there’s nothing wrong with the title. “Capacity” is mentioned specifically – if “output” was mentioned, I might be able to agree with you.
  - http://www.facebook.com/matthew.t.peffly Matthew Todd Peffly
    
    Technically 245 was all solar. PV(50) and solar thermal (large and small scale) 188. So small scale solar thermal is not 245.
  - Louis
    
    While it isn’t incorrect, considering many people don’t understand that difference, which makes it misleading. Is there a reason we should value your concurrence or are you just another internet expert trying to demonstrate how their position is the only intelligent one? Technically, this makes you pathetic.
- globi
  
  Since China has approximately 150 GWth of solar hot water capacity: http://www.map.ren21.net/GSR/GSR2012_low.pdf
  Chinese roofs deliver almost 3 times more output than Chinese nuclear power plants.