The state of residential solar power | Ars Technica
SCIENTIFIC METHOD —
The state of residential solar power
Choosing solar in a vacuum now makes sense—but location and bureaucracy still loom IRL.
LEE PHILLIPS - 2/5/2017, 8:00 AM
Don't panic, but we will need to generate approximately 15TW of usable energy from renewable (carbon-neutral) sources by 2050 in order to stabilize the atmospheric CO2 concentration. And purely in terms of available energy, solar power has the greatest potential for meeting this requirement.
Solar is "probably the only long-term supply-side energy solution that is both large enough and acceptable enough to sustain the planet's long term requirements," according to Richard Perez, senior research associate at the Atmospheric Sciences Research Center at SUNY-Albany. Perez' analysis includes geothermal, wind, all other significant renewable sources, nuclear fission, and all forms of fossil fuels.
So while wind, hydropower, and geothermal extraction may work well on a local or regional scale in certain areas, today the potential of solar exceeds any other renewable energy source by several orders of magnitude. It's simply the only contender, besides nuclear power, for a global solution to supply civilization with the massive amount of energy it demands.
On average, the power from the Sun striking the Earth's surface is 175 W/m2. If we assume that 10 percent of this incident solar energy could be converted to electricity, supplying the energy used by the United States would require covering roughly two percent of the land in the US with solar cells—that's roughly the area of North Dakota. Since this is about 30 times our available roof space, supplying the grid with electricity from the Sun means building large solar farms.
However, that doesn't diminish the usefulness of some panels on your roof. If you own your home, you have the potential to make your own electricity. You can reduce or eliminate your dependence on the power company—maybe even sell your surplus power back to it, reducing your costs further, or perhaps even turning a profit.
Given the recent change of federal leadership, it's likely a time of great uncertainty for large US solar initiatives. But individual organizations, businesses, and even citizens can still make decisions for themselves about embracing solar to a greater extent. To get a better idea about the current state of residential-scale solar power in the United States, Ars has been looking at the practicalities, the economics, and the experiences of some people who have recently turned their houses into tiny electrical generating stations. Hopefully, even if you live in a basement apartment, you might find the findings... illuminating.
Better than ever
As children, many of us have been fascinated by solar-powered calculators and watches. A few of us may even have received science kits with tiny motors attached to palm-sized solar cells. Generating electricity from light seems magical. Why can't we run the world this way?
One of the main historical obstacles to a solar-fueled civilization has been the low efficiency and high cost of photovoltaic (PV) cells—the wafers that directly convert photons to electricity. Their efficiency, or, more formally, photovoltaic conversion efficiency, is the ratio of the electric power produced by a solar cell to the power of the sunlight striking its surface.
Enlarge / One of the first photovoltaic cells, demonstrated by General Electric.
These actually have a long history. The first solar cell was invented in 1883 by Charles Fritts, who imagined his solar cells competing with Thomas Edison's growing network of coal-burning power plants. However, his cells' one-percent efficiency made this grand vision an impossible dream.
By 1954, Bell Labs demonstrated a PV panel to the public by hooking it up to a toy Ferris wheel and a radio transmitter. This device was six-percent efficient, which was a remarkable advance over previous solar cells. It was also a true "panel," with several individual cells connected together to form a solar "battery." Although it was still too expensive for widespread adoption, The New York Times was impressed, proclaiming that it "may mark the beginning of a new era, leading eventually to the realization of one of mankind's most cherished dreams—the harnessing of the almost limitless energy of the Sun for the uses of civilization."
During the '50s and '60s, research on silicon solar cells continued. Small cells began to appear during this period in some toys and consumer devices. By the middle of the decade, efficiency had doubled, but cost was still very high, especially compared with the low price of electricity at the time. A one-watt solar cell would set an early adopter back $300, while power plants were being built at a cost of 50¢ per watt.
By the end of the decade, however, PV cells would prove themselves worthy as a power source for the then-secret embryonic fleet of satellites. The Navy, initially skeptical, was won over whenthe conventional battery on the first satellite died in a matter of days. Its solar array kept it alive for years.
The high-grade solar cells used in satellites and spacecraft, although expensive, account fora small fraction of the cost of these systems, and the relatively low cost of fuel and terrestrial power during the '50s and '60s provided little pressure in the direction of reduced costs. Nevertheless, by the early '70s, solar cells using cheaper materials had been developed to reduce the cost to $20 per watt. This, combined with the energy crisis starting in 1973, created a renewed interest in solar power for Earthly purposes.
The technology was still not ready for mass adoption, however: efficiency was still only in the neighborhood of 10 percent. Additionally, it remained far too expensive.
Today, we are experiencing an acceleration of interest in solar energy, both at the residential level and on larger scales. This is due to several factors coming together: a significant decrease in cost; increases in efficiency of solar cells; an encouraging regulatory and taxation environment; widespread concern over climate change; and significant entrepreneurial innovation.
This new surge of interest comes on top of solar power's exponential growth over the past 20 years. Prospects look good for that growth continuing. In at least 30 countries, including parts of the United States, energy from rooftop solar power is now cheaper than energy from the grid—a comparison that does not factor in subsidies for solar panels.
Another factor that has helped modern adoption is that many firms market alternatives to the conventional roof-attached panel. Some companies sell more aesthetically pleasing offerings such as solar cells in the form of roof shingles (the result is a shiny roof rather than a roof with panels jutting off). At least one firm offers prefabricated "tiny houses" that are designed to appeal to several types of customers, including a segment that seeks to minimize its carbon footprint. Some of those products come with integrated solar roofs and an option to be completely off-grid.
Elon Musk has recently claimed that his "solar roof" is cheaper to install than a conventional roof, even without taking into consideration its ability to generate electricity. Such a reality would make a solar roof a no-risk choice for new construction.
Finally, homeowners are not limited to their roof surfaces. The same installation techniques can be applied to the roofs of carports and other auxiliary structures, and PV panels can even be erected in fields and backyards.
Enlarge / Remote, low power PV applications are possible—like this water monitoring station in Virginia.
By Lee Phillips, CC BY-NC-SA 4.0
Although we're focusing on individual residential solar power, we should mention the growing phenomenon of intermediate-scale PV installations. These are bigger than residential but still far smaller than utility-sized solar generating stations. In a recent drive through rural Maryland and Virginia, we noticed the occasional plot of land planted with rows of solar panels rather than filled with cornfields and cow pastures. And in fact, "solar farms" are growing in popularity as a way for communities to gain some of the benefits of solar power without requiring each individual to invest in a separate rooftop system.
The sight of them interspersed with crops made one irresistible impression. This is just the latest way to exploit the abundant, free energy of the Sun—converting it to electrical power rather than to sugar through photosynthesis.
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Ditch metal and plastic and turn to wood to save the planet,...
By Magdalena Mis
ROME, July 21 (Thomson Reuters Foundation) - For design enthusiasts worried about forests being axed for furniture, this may come as a bit of a surprise: buying a table made of wood instead of metal or plastic could significantly help cut carbon emissions, according to a U.N. agency.
Furniture, floors and doors made out of wood require less energy to produce than aluminium or plastic, and on top of that wood continues to store carbon for years, the U.N. Food and Agriculture Organization (FAO) said.
Carbon stored by wood products offsets nearly all of the greenhouse gas emissions related to their production, FAO said in a report published this week.
"It might be counter-intuitive (to use wood) because if wood comes from illegal logging or irresponsible deforestation you will be damaging ecosystems and habitats," Rene Castro-Salazar, FAO assistant director-general for forestry, said.
"But if you are able to produce firewood, a dining table or construction materials from sustainable sources, you're ... replacing CO2 intense products for better ones," he told the Thomson Reuters Foundation.
"If (wood) is extracted in a sustainable way then you can do it forever," he said on Wednesday.
Forests play an important role in storing carbon emissions in leaves, branches and soil. Meanwhile, deforestation and forest degradation account for up to 12 percent of global greenhouse gas emissions, FAO said.
Materials such as concrete, plastic or aluminium, require a lot of energy from fossil fuels to produce. Even recycling plastic is not as environmentally friendly as some people may think.
"When you are recycling plastic you use too much energy," said Nadege Nzoyem, Central Africa manager of the conservation non-profit Rainforest Alliance.
"Wood will turn into organic material if you just leave it outside," she said by phone from Cameroon on Thursday.
FAO estimates that using recycled wood in construction and then burning it as fuel could lead to a reduction in carbon emissions by up to 135 million tonnes a year, which is more than Belgium's total carbon emissions each year.
Castro-Salazar said that one of the main challenges in promoting the use of wood is to ensure that wooden products, just like other products, come from sustainable sources.
"You can have the most beautiful shoes in the world but if you don't check and they are produced with forced or child labour then you're damaging the society and the people," he said.
"You should be sure that the brand you're buying is behaving responsibly in terms of the social and labour conditions," he added.
Nadege Nzoyem said certification systems that allow buyers to verify where wood comes from and that it is sourced in a way that is not damaging forests were key.
"The only way we have (to ensure wood comes from a sustainable source) is when you see a logo of a certification scheme like FSC," she said, referring to the Forest Stewardship Council, an international not-for-profit organisation. (Reporting by Magdalena Mis, editing by Alex Whiting; Please credit Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women's rights, corruption and climate change. Visit news.trust.org)
Your phone can make it easier, with apps that use your location to tell you where to recycle items. I tried two: iRecycle and 1800Recycle, both free and both available for iOS and Android.
They share another trait. Both are offshoots of businesses. iRecycle is run by Earth911, a website that "connects advertising partners with consumers in all aspects of their daily lives." 1800Recycle is powered by Recycle Nation, a "dynamic recycling and green living-focused website," which is, in turn, part of Electronic Recyclers International. All this is to say that helping you recycle your stuff is not the first priority of the apps' creators.
IRecycle tells you where to recycle 12 kinds of items on its home screen: automotive, batteries, construction, electronics and so on. Tap on batteries, and up pops a list of 13 types, including car batteries and marine batteries. Tap on alkaline batteries, and you get a list of places that accept them; tap on a location and you get general info and a link to a map. I learned that Mom's Organic Markets take alkaline batteries. I also saw something called the Big Green Box, a mail-in recyling program, near my office. But there was no address listed other than Rhode Island Avenue, however, and when I tried to find it using the map, the app led me to Scott Circle, which does not in reality feature a Big Green Box.
Rather than listing categories, 1800Recycle starts with a search: Start typing in b-a-t-t — and up come three options: rechargeable, alkaline/single use, and button and cellphone. Tap on alkaline and you get a map with locations; each location includes an information button, which opens to list what the site does and doesn't accept. 1800Recycle's results didn't include the nonexistent Big Green Box and did include several places that were not in iRecycle's results, including Whole Foods Market. But if I wanted to recycle a car battery, I would have had to search under automotive and look at each location.
Bottom line: For the most comprehensive recycling information, you might want to download both these apps. And always call to confirm.
Happy Earth Day 2016
Earth Day is an annual event, celebrated on April 22, on which day events worldwide are held to demonstrate support for environmental protection. It was first celebrated in 1970, and is now coordinated globally by the Earth Day Network and celebrated in more than 193 countries each year.
On Earth Day 2016, the landmark Paris Agreement is scheduled to be signed by the United States, China, and some 120 other countries. This signing satisfies a key requirement for the entry into force of the historic draft climate protection treaty adopted by consensus of the 195 nations present at the 2015 United Nations Climate Change Conference in Paris.
In 1969 at a UNESCO Conference in San Francisco, peace activist John McConnell proposed a day to honor the Earth and the concept of peace, to first be celebrated on March 21, 1970, the first day of spring in the northern hemisphere. This day of nature's equipoise was later sanctioned in a proclamation written by McConnell and signed by Secretary General U Thant at the United Nations. A month later a separate Earth Day was founded by United States Senator Gaylord Nelson as an environmental teach-infirst held on April 22, 1970. Nelson was later awarded the Presidential Medal of Freedom award in recognition of his work. While this April 22 Earth Day was focused on the United States, an organization launched by Denis Hayes, who was the original national coordinator in 1970, took it international in 1990 and organized events in 141 nations. Numerous communities celebrate Earth Week, an entire week of activities focused on the environmental issues that the world faces.
Obama calls Paris climate pact 'best chance' to save the planet
"Today the American people can be proud because this historic agreement is a tribute to American leadership. Over the past seven years, we've transformed the United States into the global leader in fighting climate change," Obama said.
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Reuse, recycle, refill: writing the future with green pens
While conducting a "waste audit" on select campus trash bins, sustainability-minded Berkeley students discovered not just to-be-expected coffee-cup lids but a surprising assortment of oddball plastic items, from plastic bags to pipette trays and contact-lens cases.
"I had a whole team of four trying to figure out what each plastic was," recalls fourth-year student Kristen Klein, coordinator of the Zero Waste Research Center, a project funded by students via a grant from The Green Initiative Fund (TGIF) ."We separated the plastics out, Nos. 1 through 7," and wrote a "huge report" on the campus's plastics footprint, she says.
The Recycling Journey of the Plastic Beverage Bottle
From Canada Free Press:
You probably know that recycling a plastic beverage bottle recaptures its value and keeps it out of the local landfill. You may also know that the bottle can live a second life in a container, carpeting, playground equipment, automobile parts, sleeping bags, shoes, luggage, other plastic containers and even clothing.
But have you ever wondered exactly how the plastic bottle that you toss in the recycling bin becomes a new T-shirt or rug?
The transformation from beverage bottle to new product begins at a recycling facility that receives large bales of used plastic bottles. The bottles are compressed into bales to reduce transportation costs and energy. These bottles already have been pre-sorted, so each bale should contain only one type of plastic: polyethylene teraphthalate (PET), the type of plastic most commonly used to make pop, water, juice, sport drinks and other beverage bottles.
The Recycling Journey of the Plastic Beverage Bottle
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iBuku Pets lets you recycle your old iPhone by giving it to your kids
Sent from my iPhone!
I recycle old iPhones to relatives! You know who you are :)
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Wales passes 50% recycling target for the first time - Wales News - News from @walesonline
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Read more: http://www.cdispatch.com/lifestyles/article.asp?aid=19865#ixzz2AfJULOTO
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