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clean energy

Clean Energy

‘Clean energy’ may have a specific definition in your mind — you may think it’s synonymous with ‘renewable energy’ (i.e. wind energy, solar energy, hydro energy, and geothermal energy). This is, generally, how I use the term.

–>Note: If you’re looking for the latest clean energy news, check out our clean energy category.

However, ‘clean energy’ is actually a rather nebulous term, since there is no agreed-upon, standard definition of it. To some, clean energy also means nuclear energy. To others, it may mean natural gas. And it can even include so-called ‘clean coal’ (if you let it). As many have noted, Obama is one such person who uses this term very broadly.

Nonetheless, despite its malleable nature, ‘clean energy’ is becoming an increasingly popular term. Indeed, I think I use it more than ‘renewable energy’ now (and, as I said, to discuss the same energy sources or technologies). So, I will briefly explain why I use it like this, and why I use it so much.

Why Use The Term ‘Clean Energy’?

I think ‘clean energy’ has become increasingly popular for two basic reasons,… or maybe three.

Firstly, ‘clean’ is a simple concept, and it’s easier to use simple concepts when speaking to the public (as politicians often are when they are using this term). It implies, rather clearly, that the use of these energy sources creates less pollution, is better for the environment. That’s a little simpler, perhaps, than the term ‘renewable’.

Secondly, people like ‘clean’ things. Generally, cleanliness is considered a good thing. And, in this context, ‘clean’ is the opposite of polluting, and pollution is widely considered too be bad. So, when speaking about whatever technologies you support (even if they are not clean in some people’s eyes, such as natural gas and nuclear energy), using a term that has a very positive connotation is popular.

Thirdly,.. well,.. with the term becoming more and more popular, it just makes sense to use it more (it’s a cycle).

Now, I think many people who use the term regularly would like to steer public opinion to using it for energy sources or technologies they support. And that gets us to the next section.

Why Use The Phrase ‘Clean Energy’ How We Do?

Basically, at CleanTechnica.com, we do not see natural gas, nuclear, or ‘clean coal’ as truly clean energy.

Natural Gas

Natural gas has been documented to create all sorts of water quality problems. Natural gas production, as it occurs today, includes the pumping of massive amounts of toxic chemicals, carcinogens (that is, cancer-causing chemicals), into places they really shouldn’t go.

Leading energy and climate scientists have also specifically identified that using natural gas as a ‘transition fuel’ to get us off of coal power is a bad idea — it’s not going to be adequate enough to stop catastrophic global warming. That’s a big deal. Here’s one graphic from a recent study on the matter:

‘Clean Coal’

While I think it is important to develop carbon capture and sequestration technologies for coal, I don’ think coal could ever be considered clean. Coal is highly subsidized by you the taxpayer, and additionally costs the U.S. about $500 billion a year more than what is accounted for in its price, according to the former Director of the Harvard Medical School Center for Health and the Global Environment and 11 co-authors; the human cost of coal goes way beyond its impact on the climate, which is anything but negligible; and coal causes all sorts of other environmental problems. These days, we have gone the route of blowing up entire mountain ranges to extract coal, something that not only destroys mountains and mountain ecosystems, but also waterways and mountain communities.

Coal is not clean, even if we were someday able to capture the CO2 it emits and sequester it.


Nuclear comes the closest to being clean in my eyes. But it’s got one fatal flaw. One, it creates radioactive nuclear waste that lasts longer than humans are known to have existed for. I think it’s extreme arrogance to assume that we will be able to contain that for such a long period of time. There are other reasons for opposing nuclear energy (i.e. it’s an economic nightmare), but that’s why I don’t consider it ‘clean’.

What is Clean Energy?

So, with all that said, I do view renewable energy technologies as being clean, because they have a much, much lower contribution to global warming, and take from or harm the environment to a much, much smaller degree. I’ve seen many studies confirming this over the years.

So, basically, if you initially thought solar and wind energy when you thought of ‘clean energy’, I’m with you.

Top Image: wind turbines courtesy shutterstock.

  • Gianni Peccerelli

    Hi Im planning on setting up a 5 MW solar park in Guatemala, I need some help I have about 23 square blocks of land ready for the first part of the project land and now Im investigating everything else, local market, solar panel suppliers, etc I could use some help Im also interested In investors . My email is mediatechgt@gmail.com

  • David Alston

    I have 44 acres of land to lease for solar farming in virginia. I have another 100 acres in South Carolina. I have another 400 acres in Minas Geras Brazil for lease. dvalstn@aol.com

  • marc stanton

    The Sun Shines on Clean Power Solutions

    The sun is literally shining on Clean Power Solution’s solar PV installations. They are installing more solar PV systems than ever before and are now seeking to buy dead leads from other solar PV installers and energy consultants. Clean Power solutions will actually buy any commercial projects above 11kWp that have halted because of the cost of Grid connection or the refusal of the local DNO to allow Grid connection because of constraint problems.

    Their patented new storage and Grid connection system means that for them; they can connect ANY amount of generation to the Grid at G83/2 conditions, can not be refused by the DNO and all Grid connections have no upgrade costs. All of the DNO’s have reviewed the design and agree that it is perfectly acceptable and connections using this method are G83/2 compliant.

    Their new energy storage system means that even with the recent decimation of the Feed in Tariffs, a 50 kW solar PV system can give a return of 22% and a 5 year payback, meaning that once again solar PV is worth installing if combined with storage. It also means that for the customer, they can use all of the generated power rather than send it to the Grid and then buy it back.

    In the past, the problem has been that export or connection in constrained areas has been limited to roughly 4 kW per phase. Clean Power Solution’s new storage system allows any amount of power to be stored and fed to the Grid at G83 conditions. This patented new method is creating more work for Clean Power Solutions than they can handle in many locations and they are looking to expand their teams around the country.

    Any company that has dead leads which cannot progress because of Grid connection problems is invited to contact Clean Power Solutions on 01704 821419 x 303 to discuss your options.

  • fabius71

    For those interested in the realization of a project of solar thermal (Archimedes project) to build a large-scale can you please mail me at fguagno@libero.it

  • Vibhav

    Any way I can get a financial model to find out the financial viability of a Solar Project? Thanks!

  • a

    this is all so great and everything but who is the author
    by name and last name and contributers

  • Paul

    I am considering installing a solar electric farm on some rustic land in Spain Costa Blanca. There is an electric Sub Station on the plot. Land measures around 13000 sq metres. Any advice on costing & type of installation would be welcome. I understand Spanish authorities may be threatening breach of European Codes over feed in promises made & grants etc.

  • AIM Solar Power

    Kindly let me if you can fund solar energy projects for company in Egypt and what are the conditions for applying. Thanx for your cooperation.

  • D Dunstan

    Hi Zach
    Apologies for omitting our contact details which reads; techintegrated@gmail.com Tks and Rgds.

  • D Dunstan

    Hi Zach.
    It is our intention to build – own – operate a 1MW P V farm in Malaysia.
    It would be most appreciated if you could kindly advise us as to the current negative and positive sides to such a developmen, today
    We are a group of 3 retirees with some EPF/ CPF savings and benefits,intending to embark on a Feed – in- Tariff project with the relevant government agencies.
    As you are the ” guru”, if we may, on the subject, could you kindly advise us as to the repuitable parties we should approach ie. approved engineering PV designers / government agency registered contractors established in Peninsular and East M’sia.
    Your kind understanding and co-operation in this matter is most welcomed.

  • Richard

    ok lets start with concrete numbers. Assume 10,000,000 sq ft of so;ar panels on the roofs of commercial flat roofs in Ca AZ TX or FL (230 acres. What would that cost and how many kws would they generate. What effect would that have on the oil markets? FOr example compare with the effect shale oil has on the current market, and assume the same parameters. Compare the cost of these panels to the cost of 1 cruise missile ($500,000,000?) muck less one F16 jet. Assume that the solar panels are financed at 4% over 12 years, can be depreciated over 5 yearsby special government bonds like municipal bonds. Then imagine the effect on the GDP with all the jobs this would create.If it helps, you could increase the sq footage to 1 trillion feet or 22,000,000,acres, This is so doable in our southern states alone.
    Imagine then how many otherwise inaccessible areas could be instantly electrified such as Africa, India, Haiti, and what this would do to their development.

    Why doesnt someone make these simple points who has some scientific credibility?

    • Bob_Wallace

      10,000,000 sq ft.
      8,000,000 sq ft allowing 20% loss for space between rows.

      Picking a panel that’s just under 16% efficient
      260 watts in 17.75 sq ft
      450,704 Panels

      117,183,099 Watts
      117 MW

      5 Avg solar hours per day
      586 MWh/Day
      365 Days
      213,859 MWh/Year
      214 Thousand MWh/Year

      3,725,101Thousand MWh Total US Consumption 2013 (EIA)

      0.006 Percent US Annual Consumption

      $2.13/watt Q2 2015 Avg Cost Commercial Solar
      $249,600,000 Installed Cost

      (Always check my math….)

  • Dan8

    I have panels and love them but all this talk of solar seems to forget that the sun does not shine at night and you need either a grid, batteries or generator to run your system in the dark. The cost of all that needs to be folded into the equation. We need to look at solar as a 24/7 system, not just solar panels.

  • Richard

    what if we put solar panels on the roofs of every flat coommercial roof in CA, AZ,NM,TX,LA,FL. WHat would that reduce our usage of coal and oil per year. What would that cost to install?. What would that do to Saudi Arabia, and Russia’s GDP?
    How much would we save in defense spending?

    • Bob_Wallace

      Answering that question would take a lot of work. One would have to start by determining the area of every flat roof in all those places.

      A short cut answer is that the more solar we install, the more the price of solar installation falls. The less coal we use. As we bring more EVs on line the solar will help us cut oil use and imports. Using less oil would decrease SA’s and Russia’s GDP and, more importantly, their political power.

      How much are we spending defending Middle East oil producing operations? How much did we spend on three oil wars?

      Unknown numbers, but the results would clearly be good for us in every way. And we didn’t even bring climate change and health costs into the conversation.

  • Tanvir Ahmed

    Its a great article ..

  • Sagar Ashish

    I am doing a on solar train project and any information this topic to give me

  • Ivor O’Connor

    Seems Solar Companies are the new Used Car people. They come around insisting for a 1.5 hour meeting. Basically to just wear the homeowner down so they say “yes” to anything. Then they try to get you to sign online documents you do not have easy access to. Then they jack up the contract to 30K-40K and try to get you into contracts that will take decades to pay.

    This industry needs some middlemen to step in between the homeowner and the solar industry to keep this industry honest! Basic questions everybody should ask is how much a system costs to prevent Tier 1, 2, 3, and 4 and how long would each system takes to pay itself off if you kept paying what you currently are paying.

  • Jerry Potkanski

    Here’s an important tip. Hose your panels off at least once a week to remove accumulated bird droppings and dirt that block your panels from receiving all the possible full rays the sun has to offer. When I do, my solar production efficiency increases about 10%.

    • Bob_Wallace

      You live in a dirty place, Jerry. ;o)

    • Jerry Potkanski

      You can’t control the birds, Bob. They will do what they do. I am in the high desert far enough away from Los Angeles, that the air is quite clean, but thunderstorms will deposit a residue on your panels that matches what is on your car windshield.

      • Bob_Wallace

        At my previous house I used to have to wash off my panels every couple of days during blackberry season. For some reason birds liked to rest on top of my panels and digest bellies full of berries. This house, for over ten years, not a single bird poop.

        The need to wash panels is a local issue. Even moving a couple miles can make a difference.

  • Kathleen Martin

    Over the weekend i was driving to las vegas when i saw the most brightest tallest beacon of light coming from a tower well 3 towers total and they were all surrounded by solar cell collectors and i really couldnt tell if they were reflecting the suns light or projecting light, can you elaborate on what these 3 towers are and what they do?
    i believe they were near a town called searchlight nevada.

    • jeffhre

      “…computer-controlled mirrors roughly the size of a garage door reflect sunlight to boilers atop 459-foot towers. The sun’s power is used to heat water in the boilers’ tubes and make steam, which drives turbines to create electricity.”

  • Gerry

    (Solar Power Maker Technology Co.,Ltd) is a global high quality solar power solution supplier local in China, helping clients obtain and utilize solar power efficiently.

  • Toyin Oyewole

    Can anyone share with me a recent life cycle cost (LCC) comparison between solar and diesel generator, that reflects the latest costs and improved efficiency of solar modules

    • Bob_Wallace

      I’ll put up the latest Lazard LCOE chart that shows the cost of electricity from a diesel generator and PV solar (along with other generating methods).

      As you can see diesel doesn’t look too good.

      If you want to read what’s behind the chart here’s the link –


      LCOE isn’t really a life cycle cost analysis. It generally covers only the first 20 years of use. Since we’ve now got solar panels that are 40 years old and doing fine it’s not hard to guess that solar will only pull further ahead of the diesel generator past year 20. The solar system will require almost no maintenance and no fuel. End of life costs for solar are likely to be far cheaper.

      • Toyin Oyewole

        Thanks Bob, very useful and current information. I am trying to make a pitch to Nigerian Telecom operators

  • Guest


  • Moe

    If I buy “clean electricty” from a supplier such as Ethical Electric, my lines are still from Com Ed. They can’t separate my clean electricity from my neighbors dirty electricity,
    we share a common transformer. I don’t get it, I think it’s a scam because clean always costs more.

    • Bob_Wallace

      Your electricity is being sourced from clean sources. Your money is going to companies that own solar, wind, biogas, whatever generation. It’s not going to coal plants.

      Sure, the electrons are all mixed together. But the money isn’t.

      You’re paying (I hope) a little extra as a way to drive the market faster to renewable energy and faster away from fossil fuels. Let’s say you and others contract for all the electricity ABC Clean Wind Farms can produce. That means that they’re going to install more turbines.

      And the value of the coal plant is going to sag as they have to unload their extra power for less.

      Think of that small additional cost as a partial makeup for all the fossil fuel you’ve burned in your life.

  • SBarwal

    1MW cost you around 7-8 crore rupees in present scenario in India.

    • Bob_Wallace

      That means about nothing to most people who read this site.

      Please include either US dollars or euro numbers. It makes no sense to ask your readers to figure out what a crore is and how much a rupee is worth.

  • sami

    how can we say that sun light can be efficient


  • khalid

    how to make solar circle at home for car parking

  • Greg

    I hate it when people publish graphs that end 4 years ago!
    Apart from that “yay for solar”

    • Calamity_Jean

      The oldest comments on this article are three years old, so probably the graphs were the latest data available at the time of writing.

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  • Dan8

    I have no issues with solar whatsoever, it will pay for itself over time. And once the house solar system is installed, the infrastructure is in and the way I look at it is in 10 years or so I’ll upgrade to more efficient panels which will pay for itself faster and 10 years later… and so on. As long as the infrastructure is in, the panels are just snap in. Sure, the cost of electrons will increase but I’ll be way ahead every time

    • Satish


      I am an I.T. computer analyst and I live in Singapore. I always admire and think of doing something new or be a part of it in the green energy solution.

      I & My friend(s) always discuss this more often, and like to setup/supply with a complete solar energy power for 24hrs in India. for example government schools, mid level commercial companies. As you know, India is a country where it is rich in sunrays exposure and I dream to have these setup in india (south).

      I often follow this blog and glad to know there are great expertis in this.

      By some part, is that something we can take part as you had some projects like a channel partners or distributors or help us in a achieving the solar power to buildings?

      Please guide me and I am novice.


      email: satsix@gmail.com

      • Bob_Wallace

        There are many organizations installing solar systems in India (and other countries). I’d suggest you contact some of them and work with them. I would imagine they would be very happy to put a system in place if you did nothing but provide the financing.

        Try spending some time googling organizations such as the International Solar Energy Society, contact them and see if they can give you some leads. Or try Solar Electric Light Company, India. Even contact the Indian government, they are very pro-solar.

        And do a search using “micro solar in india”. The micro-solar movement is, I think, what is going to make the largest impact on the lives of the most people. The concept arose in Bangladesh and has great results to date. Here’s a bit on what’ happening there.

        July 2013 (more than two million now)

        “Over the past decade, since the Bangladesh government launched a rural electrification programme supported by the World Bank and other international aid bodies, the number of off-grid installations in the country has rocketed. In 2002, installations rates stood at 7000; today that figure has exploded to nearly 2 million and counting, with average installation rates now topping 80,000 a month.

        “A typical customer would give a 15% down payment, and then the balance would be made over a period of 24-36 months,” he says. “A typical system would be 50W – for LED lights, a black and white TV connection and mobile phone charger, with four-hour back-up up every day. The cost of everything would be US$300-325, and a household would typically pay US$8-10 for that every month.”

        Moin says that even being able to power these relatively modest appliances makes a big difference to people’s lives. “It’s unbelievable, and until you see it, it’s very difficult to explain. Let’s say you go to a rural remote home and they’re burning kerosene lights, suddenly overnight (because it only takes four hours to install a typical system) that home has proper lights and connection to TV – it’s transformational. And the quality of life keeps on improving – in terms of late hour education, and even in shops, they’re keeping them open later into the night.”

        Although developing this local supply chain has been a key part of the success of the Bangladesh programme, Moin says other countries looking to follow its example should not get too hung up on localisation initially.

        “Do exactly what we did,” Moin advises. “Have the initial pilot phase, don’t worry about localisation, build it up to 40-50,000 installations, and then at the same time make sure the localisation happens as the volume increases. Once you hit 50-100,000 systems in a market, and the market gives you consistently 10-20,000 a month, localisation is absolutely feasible.”

        Moin is already beginning to travel the globe advising other countries on how they could develop a programme along similar lines to Bangladesh’s: “The idea is to show to the world that there are south-to-south models that can be replicated; the traditional model is north-to-south, but we believe there are models, especially with bottom-of-the-pyramid rural energy access needs, which can be done on a south-to-south model. So let’s look forward.”


  • I recently read an article (“The catch-22 of energy storage”) on the TheEnergyCollective, stating that the energy returned on energy invested (EROEI) for solar power is too low to be economically viable as an energy source for an OECD level society. What is your take on this?

    • Bob_Wallace

      My take on you finding something that wrong on The Energy Collective?

      I’m not at all surprised. They publish very flawed articles quite regularly. There’s a very heavy pro-nuclear, anti-renewable energy bias on that site.

      The number of years to payback varies depending on the technology. Silicon panels take a bit longer than thin film panels. And payback will depend on the amount of sunshine where they are installed. Payback will happen quicker in sunny SoCal than in the less sunny Northeast.

      And payback times have been dropping as manufacturing becomes more efficient. IIRC, the first panels required more energy to manufacture than they produced in their first 40 years of use.

      Let me copy out part of a 2012 study and give you a pay back graph from it…

      “EPBT (energy pay back time) for the same type of systems installed in the U.S. Southwest are decreased in proportion to the solar irradiation ratio (1700/2380) between the U.S. average and Southwest solar conditions. Thus, for Southwest irradiation the EPBTs for the three PV technologies shown in Figure 3 are 1.2, 1.2, and 0.5 years and the corresponding EROIs are 0.04, 0.04, and 0.02, thus 50 times better than stated in the July PE article. And these EROI keep improving as systems and material utilization efficiencies continue to improve.”


      Six months to 1.2 years.

      And an example of how EPBTs have decreased as manufacturing has become more efficient, here’s an earlier (2008) study that found –

      “The study shows the EPBT for standard, single-crystalline module PV systems to be two years. For PV systems using multicrystalline modules produced by the casting method, the EPBT is calculated at 1.7 years. PV systems with modules produced using the ribbon method reduced the EPBT to 1.5 years.”


      “Ribbon method” is thin film.

      • Bob_Wallace

        From a common sense level – the energy embedded in a solar panel is going to be reflected in the cost of the electricity produced.

        All the energy it takes to extract and smelt aluminum for the frame, to melt the silicon for the active part of the panel and the cover glass, all that energy has to be paid for. No one contributes aluminum, glass and processed silicon to the manufacturer for free.

        The materials cost plus manufacturing costs, including energy, are passed on from the manufacturer to buyers.

        Solar is now our third least expensive way to generate electricity. Only wind and natural gas are cheaper. If solar panels never repaid the energy that went into them then the cost of their electricity produced would be very, very expensive.

        As it was for solar panel early use. A lot more energy went into panels that powered satellites than was ever produced. But solar panels were the easiest to get into orbit, making their high cost reasonable.

        • Do you have a reference for the comparison of energy production costs?

          • Bob_Wallace

            I’ll copy over some stuff on wind, solar and nuclear. I don’t have a current price on natural gas.

            Present cost of wind, solar and nuclear

            Wind = $0.04/kWh average 2011 and 2012 PPA. Without subsidies that’s roughly $0.055/kWh.
            DOE “2012 Wind Technologies Market Report”


            And then wind falls in the next year. Wind = $0.025/kWh average 2013 PPA. Without subsidies that’s roughly $0.04/kWh
            DOE “2013 Wind Technologies Market Report”


            Solar = $0.05/kWh PPAs being signed in the US Southwest. Working backwards through a LCOE calculation extrapolates a cost of about $0.02 higher for the less sunny Northeast. Without subsidies that’s a range of roughly $0.065 to $0.085/kWh.

            Lawrence Berkeley National Laboratory entitled “Utility-Scale Solar 2012: An Empirical Analysis of Project Cost, Performance, and Pricing Trends in the United States” http://reneweconomy.com.au/2013/big-solar-now-competing-with-wind-energy-on-costs-75962

            PPA prices for wind and solar are lowered about 1.5 cents by PTC (Production Tax Credits). Both wind and solar are eligible for 2.3 cent/kWh tax credits for each kWh produced during their first ten years of operation. Half of 2.3 is 1.15, but getting ones money early has value.


            An analysis of the Vogtle reactor costs by Citigroup in early 2014 found the LCOE for electricity from those reactors will cost 11 cents per kWh. That is assuming no further cost/timeline overruns.

            They also stated that reactors build after the Vogtle units would likely produce more expensive electricity as they would not be able to receive the low financing rates as Vogtle has obtained.


            That 11 cents is a subsidized price. Nuclear receives federal guaranteed loans which lets it borrow money at rates better than wind and solar. Nuclear also only has to provide insurance against the first $12 billion of a disaster, should one happen. Taxpayers would have to pick up the rest of the cost. Fukushima is likely to cost far more than $100 billion.

      • Hi Bob, I’m by no means an expert on solar power, so I appreciate you taking the time to give me a more nuanced picture of the technology. Perhaps you could answer the following question for me? What are the current limitations for reducing the energy (cost) of producing solar panels even further? Can future shortages of silicon put a stop to development of even cheaper panels or are there already alternatives out there?



        • Bob_Wallace

          No problem, Ed.

          The price of solar panels has fallen incredibly rapidly.

          Best I can determine it costs about 50 cents per watt to manufacture silicon panels these days. Thin film is likely a bit less. Prices are expected to fall further. First Solar, a maker of thin film panels, has said that they will have their costs down to about 35 cents in 2016 or 2017 (I’m not sure on the exact pennies or year. Just off the top of my head.)

          At this point it’s not panel price but balance of system (BoS) costs that are the largest part of an installed system.

          At the end of 1st quarter, 2014 the average cost of a residential solar system in the US was $4.56/watt and the average price for utility scale solar (solar farms) was $1.85/watt.

          Everything over roughly $0.75/watt is BoS costs. That’s permits, inspections, racks, inverters, wire and labor.

          Other countries have managed to get their costs much lower. Residential systems are being installed in the UK, Germany and Australia for less than $2/watt. Less than half our average. Italy has been installing utility scale for about $1.30/watt and China for $1.03/watt.

          Some US utility scale is apparently now around $1.50 so we’re getting there.

          It is expected that utility scale will fall below $1/watt and residential somewhere around $1/watt over the next few years.

          There are a number of other panel technologies that are being developed but silicon is getting so cheap that it’s hard to see how another technology could get established. The new something would need to be much more efficient than silicon (now reaching ~20%) so that it could cut BoS costs. (Less money spent on racks, shipping, labor, etc.)

          Can’t see how we’re ever going to run out of materials for silicon solar panels. Sand. Aluminum ore. Bit of silver for the connections which may be replaced by graphene down the road.

          • Bob_Wallace

            Here’s a site you might want to look at. It’s the history of average system prices in Germany from 2009 to today.


            Germany is averaging 1.35 euros or about $1.77/watt. We’re trailing them by 2-3 years in terms of price decrease.

  • KjAndersson

    Strange how you treat bioenergy on your website – like almost not existing. Why is bioenergy not included among the renewable energy forms? What is so suspicious about using living plant systems to trap solar energy?
    I come from Sweden, where bioenergy today accounts for 33 percent of the final energy use. We have very little solar radiation for several months, but the trees can produce a lot of bioenergy during our sunny summers. This energy, stored in the wood, can be used during our cold and dark winters. To me this is truly renewable, and the cost is low compared to most other renewable energy systems.

    • Bob_Wallace

      Bioenergy is not as developed in the US as in parts of Europe.

      Many parts of the US no longer allow wood stoves or fireplaces due to the particulate release.

      We do have some biomass electricity production. And some of us do heat with wood, but we’re very much in the minority. (Warm night tonight, my stove is getting a rest.)

      • KjAndersson

        I am sitting on the train between Stockholm and Gothenburg – a beautiful spring morning. Every single town I pass has a heat plant using biomass as fuel (wood chips, bark, sawdust, SRC chips, etc) for district heating. Often located right by the train track. The bigger plants are CHP:s producing electricity as well. This is modern bioenergy. The forests and fields are efficient solar collectors. Bioenergy is as much renewable energy as solar, wind, hydro and geothermal. Include bioenergy in your website and on your charts!

        • Bob_Wallace

          Read the site more.

          Bioenergy is regularly covered.

          And we have electricity plants running on wood waste. One is about 30 miles from where I’m sitting right now.

  • Jef Franklin
    • Bob_Wallace

      No naked links, please.

      If it’s important then tell people why.

  • yu tube

    for me the article lost credibility the moment I saw the power circle chart. That huge circle representing solar is the total hitting the earth, now unless we cover the oceans with panels knock 70% off the total energy number. Then just look at the controversy of covering just a few tens of acres with solar panels and how it will devastate the desert tortoise. Imagine the opposition of covering old growth forests!
    When biased information like that is published it diminishes the ability to have a useful discussion of the benefits of solar power and how it can be incorporated into the power generation industry.

  • Bioleux

    I am aghast at your omission of renewable biowaste as Clean Energy.
    Despite the fact that you can actually get your hands dirty handling it, it is as clean as solar or wind, and actually helps getting our environment CLEANER.
    Not to mention more practical, as it can be generated 24/7 and stored.

  • Mukesh Bhati

    i m student of b.tech final year n my project is based on solar steam power plant n heat combustion method plzz give me me particular direction for working best in my project

  • Dinesh

    can we join OLED technology with OPV cells in mobile phones to develope a solar powered app for smartphones?

  • ukaway

    I’d be interested to know what readers think of this:


    • jimbo

      If you’re convinced your ideas are valid it should be easy enough to build a small scale test setup to verify.

  • ColinG

    Where does biomass/biofuel sit in the spectrum of “clean” energy?
    Renewable yes, but “clean”?

    • Bob_Wallace

      Clean in that the carbon released was already above ground.

      Could be some particulate problems like we have with diesel and gasoline.
      “Cleaner” is probably the best description.

      I doubt we can get people to give up intercontinental air travel and shipping. That probably locks us into some biofuels.

  • this is right and good

  • very nice vision

  • Meerwind7

    Largest Solar Photovoltaic (PV) Power Plants:

    Add Neuhardenberg (Germany) 145 MW
    Eberswalde/Finow / Schorfheide (Germany): 84,5 MW


    • Thanks. Not everything makes it to English sites. 😀

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  • Jkolle

    What is a GWp

  • The primary problem with renewable energy was and still is the increased ‘use it or lose it’ issue. With coal, nuclear gas etc production can be halted or increased (within limits) to account for demand. This is also true with renewables but there are now two not one ‘use it’ bottlenecks. The elements provide the first…the sun does not always shine, the wind does not always blow…and this coupled with the fluctuations in demand requires somewhere for this energy to be stored…. So mass battery storage is required to remove that second bottleneck…and it will also aid in removing partly the first bottleneck. This ‘storage’ issue being solved is the one that will cut costs considerably. Thankfully there are people working on this very issue at an industrial storage level.

    • Yeah, the storage needs are growing, and it’s good news that a lot of folks are working on this issue.

  • Abdul_azim17

    India is a country where there is sunshine for more than 300 days in a year and hence has maximum potential to make use of solar pv power.But not much progress is made in India to harness the solar power except for the Gujarat plant credit for which must go to its CM Narendra mody.I would like to take up distribution and marketing of these products in India as I have an engineering background if Iam offered an agency by a suitable organisation

    • Abdul_azim17

      My email I’d may be corrected as abdul_azim17@yahoo.com

    • Good luck to you!

    • Bob_Wallace

      Jump the queue.

      Take your engineering background and start a program that brings solar to the people who live off the grid.  

      It shouldn’t take a lot of capital.  You need some very basic solar systems (small PV panels, controller, batteries, LED lights) to bring light and cell phone charging to a home now operating with kerosene.  

      They can pay you for your solar system with part of what they were paying for kerosene, you make money and they have better quality light and a bit more money in their pocket.

      A few years of hard work and treating people right and you’ll be a “suitable organization” and have the satisfaction of knowing that you made a lot of people’s lives better.

      Here’s a company already doing what I suggest.   India has room for many, many more companies like this one…


    • christopher

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  • Arjaytech

    Wow, that was pretty awesome.


  • Solare Solare

    Please update your Solar Growing Rapidly graph to show 2011’s data – 28GW installed. The graph becomes even more steep.

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  • Wow – brilliant information. How much more price competitive would this be if we enacted fee and dividend like the Citizen’s Climate Lobby is proposing — charge a flat $10 on each ton of carbon emitted and gradually increase the price, and refund 100% of the money collected to the American people! Economist say that 2/3rds of households would get more money back than they pay in slightly increased energy costs ($0.13 per gallon of gas, initially).

    At this rate solar is going to be at grid parity with or without this law, but it’s still a law we ought to get passed.

  • Dan8

    No matter how you spin the data and people will spin the data, the reality is that solar still has an approx 20 year return on your investment, 15 with the rebates. That’s the worst investment a person can make especially in a moving technology. If you have the money to throw away, fine, otherwise it’s a foolish venture. Wait until the ROI is 3 years or less.

    • Dan, there are plenty of places where its far less than 20/15. In some it has gotten down to a few years. There are also leasing options where you’re saving money from Day 1.

      • Dan8

        Well, I’m totally skeptical. Let’s be a little more to the point. Just to see what’s happening in the market I’ve gotten 2 bids each year for the last 3 years to totally solarize my So Cal home. My electric bill averages about $300 a month. I choose to go to only reputable vendors that have solid products, will be around for the next 20 years and guarantee their work and products. The price range quoted for the entire 3 years for all vendors is between $75,000 and $85,000 after rebates. You don’t do any better recouping your costs by leasing after you look at the fine details.
        Can you give us some similar concrete examples of what you say are a ‘few’ years and how many is a ‘few’ years. I do think the Dow product is good but I suspect the cost is even more prohibitive otherwise they would be posting their prices. Since there are some Dow installations already, why can’t you get some numbers for us otherwise this is all more hype. The devil is always in the actual numbers. Solid facts don’t lie.

        • http://www.energymatters.com.au/index.php?main_page=news_article&article_id=1837

          “A recent report from the USA has found return on investment from solar power is higher than any other renewable energy source.

          The report entitled “Global Solar Inverter Markets”, released by SBI Energy,
          states the payback period for a typical solar PV-based project has reduced from 7-10 years to 3-5 years currently.”

          Estimate for a house in AZ with a 6.7 year ROI: http://cleantechnica.com/2011/10/06/laymans-guide-to-arizona-solar-rebates/

          We are planning a piece looking at solar leasing vs going solar on one’s own in more detail.

          • RobS

            Discussing specifics is difficult without a lot of info but here goes.
            $300/ month at an average Californian retail rate of 15c/kwh suggests you use about 2000 kwh per month, it should be noted at this point that is about 66kwh per day whilst Californian households average 24kwh/day consumption. It is inevitable that given you use 3 times the Californian average a system to supply all your needs will inevitably be unusually large, measures to significantly reduce that consumption including more efficient lighting etc would likely be cheaper than simply buying a bigger system, however for the purpose of this discussion let’s just continue with your current consumption.
            http://www.wholesalesolar.com/gridtie.html is the website I shall reference for system costs, they are based in California and have a large selection of grid tied systems. You will see that that you will need ~15kw system to produce 2000kwh per month. They have a range of systems between 14.5 and 15.5 kw ranging from $28,000 to $32,000. Add ~30% for installation taking you to ~$40,000 pre rebate, with the 30% rebate your looking at about $30,000. Now let’s ignore feed in tariffs which are usually generous in southern California and will significantly reduce payback time, even at your normal rate this system will save you ~$300 monthly so $30,000 will take 100 months or 8 years 4 months to pay itself back.

            Looking at this from the point of view of an investment as you initially framed it this $30,000 system generating $3,600 of power saved annually is returning 12% annually, however as that is cash saved rather then money earned it is tax free. To earn $3,600 after tax from $30,000 capital would require an investment return of ~$5,100 or a return of 17%. If you can show me in investment that consistently returns 17% with little to no risk as long as you have your system insured under your home insurance then I’ll happily admit you were right that solar is a poor performing investment. Remember the returns we have discussed thus far is the equivalent of dividends there are many studies showing that solar systems have a significant effect on your homes capital value which will further increase your return on investment.

          • Thanks for the breakdown, RobS — this is great! & worth a full repost. Any interested in changing/adding anything before I publish it as a full post?

          • Dan8

            As I said, the devil is always in the details. Those are DIY based numbers you quote, not from a full service dealer that will install and guarantee the system end to end for it’s lifetime. I talked to these DIY folks and they are providers for people that want to do it themselves, they can provide complete DIY kits but no installation or guarantee of the entire system. That makes the (large) investment high risk. That’s exactly what people need to avoid. My numbers from full service dealers stand. If I were capable to and adventurous, yes I would take on the project myself.
            This issue triggered a phone call to 2 more dealers to get a 2012 estimate. Will be interesting to see if things have gotten any better.

          • Let us know what you find out! Curious to see the details in your case.

          • Dan8

            Well I’m baaaack, a bit humbled by the way. The difference between the early and the latest solar quotes is and was amazing and I ended up with a system for about $35K using a reputable installer and a 6 year return on investment of 23%. My electric bill averages $1.50 a month. So I hope you all forgive my bone headed insistence about costs; I just had not updated my data.

          • Bob_Wallace

            That’s great news, Dan. Thanks for bringing it.

            What size system did you install? (Looking for a $/watt number.)

          • Dan8

            From the System Specs:
            $4.8/Watt DC

          • Which provider was it?

          • Matt

            “Add ~30% for installation” was for the installer

          • Dan8

            And if Zachary wants to post the info, he needs to point out all the facts, not just those favoring one side or the other.

          • Matt

            Thanks Rob

        • By the way, for this kind of money you could buy 10-15 kW of nuclear generating capacity in USA, 20 kW in Korea and 50 kW in China (of constant power, of course). With useful life of 80-100 and not 30y. PV are good for niche applications, for providing isolated communities and even some of peak power, but for heavy industry and great conurbations… Well, give me a break.

          • Bob_Wallace

            Your right. Large industrial machines discard any electrons coming from solar panels and accept only electricity coming from coal and nuclear plants.

            Thanks for sharing your wisdom….

          • Drink a glass of milk. It helps.

          • predrag, in all seriousness, we’ve dismantled all of your wild claims for why nuclear is the energy option of the future. no one here is being swayed by bad arguments. stop trolling the site with your nuclear propaganda.

          • Matt

            No Nuclear plant built to date has lasted 100 years and none have calmed they could.

          • Bob_Wallace

            Just adding some detail. No nuclear plant has operated for 50 years. The first one will reach 50 years in 2019, the year the plant is scheduled to close.

          • sivadasan

            What is the Uranium reserve as confirmed now which is economically viable.

        • JamesWimberley

          It’s possible you are unnecessarily keeping the costs high by being too restrictive on suppliers. Few of the companies selling solar panels today are certain to be around in 20-25 years, the conservatively expected life of a system. But all you need is an American insurance policy on the guarantee. For O&M – mainly replacing inverters when they fail earlier – there is no great advantage to using the original installer. Are you insilisting on buying American? The quality standards of first-tier Chinese manufacturers like Trina are good enough for Warren Buffett, they should be good enough for you.

    • Tmar2

      Stand by to stand by. Even here in Fl. where FPL owns the state and our incentives are horrible comparatively, I now have a $42/mo. avg bill. Internal reduction of kWh needs is primary. solar water heater, leds and a few little things, bam I win. Sit on the fence and talk about it, the fence will turn to barbed wire.

    • Solare Solare

      Tier 3 is $0.30/kWh here in San Diego. To get a 3 year return you can afford $0.90 plus the $.20/W rebate plus the 30% ITC or about $1.50 in total. This is how much the components cost today, so go out and get a system and install it yourself.

    • philofthefuture

      Depends on location. I put in 30KW. I shopped the internet, then self installed. With that I got the 30% tax credit. I also get $5000/yr. in state rebates. Combine that with net metering and my payback is only four years. In addition, the state sill will pay $5000/yr beyond when it’s paid for so I’ll be making thousands in addition to free electricity. If the state extends the incentives beyond 2020 I could be making some serious money!

    • John Brigance

      If you read the article clearly you would note that there is a health and environmental cost to coal and other fossil fuels, which needs to be calculated as part of the costs of production. This is why carbon taxes are now being introduced in many locations.

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  • Bngautam16

    In our faith we worship as Sun God ,life sustainer life protector .Potentials of its energy r sufficient 2 meet energy reqirements of Earth.Former President APJ Abdul Kalam has proposed several energy projects predominantly Solar Sattelite in space 4 harnessing Solar Energy.During his Presidency our magificiant Rashtrpati Bhavan was powerwd by Solar Energy—–arole model 4 our planners

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  • Rajesh

    Sir, i want to construct some solar tree, please give me the suggestion ,what is the cost of a solar tree. thanks

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