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Renewable Energy

All things energy, from solar and wind power to efficiency and off-grid living.

Can Solar Power the World?

By Dan Chiras 

Tags: solar energy, solar hot water, solar electricity, passive solar, wind, hydro, geothermal, and biomass, Dan Chiras,

Although solar electricity and wind energy are growing by leaps and bounds, they only provide a tiny fraction of today’s electrical demand. As global supplies of fossil fuel resources decline and as concern over global climate change increases, however, solar electric systems could become a major source of electricity, along with wind and a host of other renewable energy technologies. But is there enough solar energy to produce enough electricity to meet our needs?

Cow in front of wind turbinesAlthough solar energy is not evenly distributed throughout the Earth, significant resources are found on every continent. 

“Solar energy’s potential is off the chart,” write energy experts Ken Zweibel, James Mason, and Vasilis Fthenakis in a December 2007 article “A Solar Grand Plan” published in Scientific American magazine. Only two billionths of the Sun’s energy strikes the Earth, but as they point out, the solar energy striking the Earth in a 40-minute period is equal to all the energy human society consumes in a year. Solar electric systems on our homes and businesses or giant commercial solar systems could provide us with an abundance of clean energy.

Zweigbel and fellow authors present a plan that would enable the United States to switch from coal, oil, natural gas and nuclear power plants to centralized PV systems. According to their estimates, their plan could supply 69 percent of the country’s electricity and 35 percent of its total energy by 2050. This, they assert, would require a subsidy of $420 billion from 2011 to 2050 to pay for the infrastructure and make it cost competitive. Compare that to what we have spent in the Middle East trying to secure oil. But could solar electricity every provide 100 percent of the U.S. or world’s electrical energy needs?

Yes, it could.

Will it?

Probably not. 

In fact, no one’s planning on a 100 percent solar future. Rather, most renewable energy experts envision a system that consists of a mix of renewable energy technologies such as solar hot water, solar electricity, passive solar, wind, hydro, geothermal and biomass combined with radical improvements in energy efficiency.

In this sustainable energy system, PV systems could play a significant role. They could produce enormous amounts of electricity for homes, businesses, farms, ranches, schools and factories. Large-scale solar thermal electric systems could also play a huge role. Solar thermal electric systems concentrate sunlight energy to generate heat that’s used to boil water. Steam generated from this process is used to spin a turbine connected to generator that makes electricity. Some of the newest solar thermal electric systems even store hot water so electricity can be generated on cloudy days or during the evening.

Wind turbines could also provide a significant amount of electricity to power our future, perhaps even more than PVs. There’s enough wind in North and South Dakota to meet all of America’s electrical energy demands.

Geothermal and biomass resources could contribute as well. Biomass is plant matter that can either be burned directly to produce heat to generate steam that’s used to make electricity or converted to liquid or gaseous fuels that can be burned to produce electricity or heat. Hydropower will continue to contribute to the energy mix in a renewable energy future. What will happen to conventional fuels such as oil, natural gas, coal (burned as cleanly as possible) and nuclear energy?

PV CellAlthough their role could diminish over time, these fuels will be part of the mix for many years to come. In the future, they could be used to back up renewable energy technologies that generate electricity.

Despite what critics say, solar energy is an abundant resource and many forms of solar energy are affordable right now. Solar energy will very likely play a major role in our energy future. It has to. Fossil fuels like oil are finite. In fact, conventional oil (crude oil, not shale oil) could be economically depleted within 30 to 50 years. Many energy experts believe that crude oil supplies are already on the decline. Natural gas supplies are on the decline, too. In fact, U.S. natural gas production peaked in 1973. Some energy experts believe that global natural gas production could peak between 2015 and 2025. Coal, which is abundant, is still a finite resource and, lest we forget, a major source of the greenhouse gas carbon dioxide, the main cause of global warming.

The sun, on the other hand, will continue to shine for at least 5 billion years. With 30 to 50 years of oil left and 5 billion years of sunlight, what’s the future going to look like?


Top: There’s enough wind in North and South Dakota to meet all of America’s electrical energy demands. Photo by Kathleen Stuart. Bottom: As global supplies of fossil fuel resources decline and as concern over global climate change increases, solar electric systems could become a major source of electricity, along with wind and a host of other renewable energy technologies. Photo by Dan Chiras. 

Contributing editor Dan Chiras is a renewable energy and green homes expert who has spent a lifetime learning life’s lessons, which he shares in his popular blog, Dan Chiras on Loving Life. He’s the founder and director of The Evergreen Institute and president of Sustainable Systems Design. Contact him by visiting his website or finding him on .

3/23/2010 12:43:23 PM

I have studied this topic since the first oil embargo of the mid 70s. From an economic perspective, there are tactics and inducements that could help the individual homeowners absorb the immense up-front expense of the systems. The govt is now offering real tax incentives and that is a great step. Besides tax rebates, there needs to be some kind of financing help. Govt-backed loans for financing of systems over ten years would take much of the pain away from that initial cost. Building codes would also be an approach where improved efficiency measures would get us further toward our goal of efficiency. Thomas Friedman put it into clear perspective when he wrote the book 'Hot, Flat and Crowded'. He makes a great argument for action in implementing a transition to alternative energy. First, it is ludicrous to think that drilling for oil on our own soil will wean us from our dependance on oil for energy. Oil companies will take what they extract and sell it at market rates so, except for jobs, there will be no positive outcome. Whether we consume domestic oil or imports, we still prop oil up at its current price thus financing terrorist groups indirectly. AE will also finance permanent jobs. Unleashing the innovative power of the American people will also position us for decades as a major exporter of new technology that will also boost our economy tremendously. Not to mention that global climate change is indeed real.

b knight
3/21/2010 7:51:09 PM

Can Solar Power The World? Yes it can. I think it would be more realistic to say Renewable Energy Can Power The World. Now is the time to act - make a difference. If you only look at your pocket book - what will it cost ME? Then spend the money on efficiency gains - insulate to reduce heating and cooling. Use LED or CFL lighting. Reduce your driving - trade that gas guzzler in, use public transit, bike and walk. If you are ready for the next step, install solar thermal water heaters. Then look into a solar PV electric system. Here are some pictures from my solar PV system we installed this week..

jos van doorn_1
3/21/2010 12:13:05 AM

Yeah. Renewable energy. Forget about it. Renewable energy will never be used. Not as long there is still oil. Let me tell you why. Every country in the world has got a president or a prime minister. They are supposed to run the country. But they do not. They are puppets. Every country is run by powerful organizations. The oil compnanies are one of those powerful organizations. They stop the use of the renewable energy. Wait. In the US you have got senators and members of congress. Could they stop them? Are you kidding? They are paid to shut up. For the US I can say it is time to votte for a man that wants to stop the powerful organizations. Obama? Forget about Obama. He is a puppet. There were presidential elections. Obama made a lot of promises. Now he is president. His promises? Obama is doing nothing about them. Obama is a true politican. Promise the nworld and do nothing. But then he is afraid of getting killed. See RFK, Bobbhy Kennedy, and MLK.

jim bell
3/20/2010 1:01:52 PM

Before we do mass and especially remote installation of renewables, we should exhaust all cost-effective efficiecy measure in our buildings and infrastructures and cover all suitable roofs and parking lots and perhaps some roads with PV panels. + Efficiency in buildings and local PV installations create local business and employment opportunities. They also eliminates the need to scrape off large tracts of wildlife habitat to install PV, wind and other renewable energy options and build the access roads and transmission lines to support them. + Additionally, because locally owned business owners and the people they employ live locally, most of the money they earn will be spent locally too. This creats indirect job and business activity or a positive energy-purchase-cash-flow. For example, in San Diego County we do have a number power plants fueled by imported natural gas to makes electricity. At 10 cents per kWh, 8.7 cents of the 10 cents we paid for it is used to purchase imported natural gas.

nora _1
3/19/2010 5:38:58 PM

I just had lunch today with a very dear friend of mine who is now a rep for a solar company. He was telling all of the wonderful thing that solar can do and with a four bracket system I could supply electricity to my entire neighborhood. I was sold and told him I wanted it. He then informed me that they were not allowed to sell it to residential consumers because my current electric company will not allow it. In other words his company cut a deal with my electric company not to sell to me. I thought I lived in America where if I had the money I could get whatever I wanted. Nice to know that I really don't have the freedom I thought I had. BTW he told me that the profit margin on the solar panels is through the roof. It could be cheap, but that would be unamerican.

peter jones_1
3/19/2010 2:15:44 PM

I think we all really need to stop relying on central government to do what we all know needs to be done.And what needs to be done ,is that we all need to be independant and get solar and wind power systems for our own homes. If we wait for government we will surly lose our planet and we know it. Get the system installation done and take the tax credit. You cannot rely on politicians,you never could and never will be able to. Not being negative,just realistic. In short, action by individuals is what is required.I know I'm talking to the right people,people who know what it is to decide their own destiny. Peter

finula mccaul_2
3/19/2010 12:38:34 PM

I beg to differ on global warming, and encourage people to think about what they hear, rather than believing something because they read it or hear it. This goes for both sides of the argument. Look at primary data. The truth is that the Antarctic ice cap is breaking up. Ice that has been solid and stable for thousands of years is disappearing. The same is true of the northern ice cap. There is now so little ice left that polar bears may soon become extinct. America, unfortunately, tends to be shortsighted in its economics. Yes, you can use up all the oil, gas and coal in the next few decades, lowering prices and biodiversity at the same time. But then those resources will be gone. What will your children use? If you have any family at all, think about the future, and support research in things that are sustainable, for the sake of future generations. Finula

3/19/2010 10:22:17 AM

Like many people, I love the idea of our country being energy independent. Just think no more foreign fossil fuel! If everyone could afford to install solar panels and/or wind turbines, we would reduce our use of foreign fossil fuels, help stop terrorism and clean up the environment as well! Its a win/win/win. We need to find a way to make these green technologies more affordable for everyone. Until then, I will continue to save up my money for the day I can afford those awesome solar panels.

fran tracy
3/19/2010 8:14:47 AM


3/13/2010 4:51:35 PM

Good post Dan. I think if we first re-examine our housing construction and start considering more efficient, sustainable alternatives like straw bale, earth bag, or rice hull, energy use would be drastically reduced due to their tremendous insulation properties. This combined with, as you pointed out, the multiple RE resources and we really should be on the right track. Reboot2009