New Smart Tinting Windows Become Solar Panels When Changing Color

An amazing new solar power technology can turn skyscraper buildings into giant solar power plants. 

Currently, these buildings use Low Heat Emission (Low-E) glass windows to reduce overheating and air conditioner costs during warm seasons. According to the U.S. Office of Energy Efficiency and Renewable Energy (EERE), such windows are in 80% of homes and 50% of commercial buildings. The National Renewable Energy Laboratory thinks this is a giant wasted opportunity because they figured out a better way to use those UV rays. They invented a glass window that still keeps heat out but also turns the sunlight into electricity at the same time. 

Smart Tinting Solar Windows

NREL's prototype changes color when the glass gets hotter; this is called being thermochromic. When the sun heats the window, methylamine molecules are pushed out, darkening it. They're made from the energy-harvesting material perovskite and maybe in all the windows of the future.

“There are thermochromic technologies out there but nothing that actually converts that energy into electricity,” NREL scientist Lance Wheeler said in a press release.

The inner workings of this “smart window” technology. Image Credit: NREL 

NREL's team of scientists tested their prototype and published a report in the Nature Communications. It turns out this new solar window is 11.3% efficient converting sunlight into electricity. This is pretty low compared to the best solar panel at 46%, but it's better than the 0% windows were getting before.

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“There is a fundamental tradeoff between a good window and a good solar cell,” explained Wheeler, who is a lead researcher in this study. “This technology bypasses that. We have a good solar cell when there’s lots of sunshine and we have a good window when there’s not.”

 

Clear Future Turning Dark?

Considering a large office building has more square footage of windows than it does on its roof, the 11.3% efficiency multiplied by the large surface area can make a big difference to the building's energy bill.  According to Electrek, 80% of facility energy costs are spent on heating, cooling, and ventilation.

While this all sounds like this may be a path to a clear bright future, things may, ironically, turn dark. So far, at least, NREL’s solar-powered smart windows stop working after 20 color changing cycles. This is a major dealbreaker and no one will install solar power windows that last less than a month. To put it in perspective, standard solar panels maintain their effectiveness for 25 years. 

Again though, the potential here is huge, so if NREL figures this out, it'll be well worth it. Besides replacing commercial building windows, these could replace car windows as well; maybe even sunglasses. 

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Sources:

NREL, Nature Communications

World's Largest Battery Built in Australian Outback by Tesla

ADELAIDE, Australia (AP) — The world's biggest lithium-ion battery has plugged into an Australian state grid, an official said Friday, easily delivering on Tesla Inc. chief executive Elon Musk's 100-day guarantee.

Musk promised to build the 100-megawatt battery within 100 days of the contracts being signed at the end of September or hand it over to the South Australia state government for free.

South Australia Premier Jay Weatherill announced Friday the battery began dispatching power into the state grid on Thursday afternoon, providing 70 megawatts as temperatures rose above 30 degrees Celsius (86 degrees Fahrenheit).

"South Australia is now leading the world in dispatchable renewable energy, delivered to homes and businesses 24/7," Weatherill said.

The official launch came a little over 60 days after the deal was signed. But crucially, it came on the first day of the Australian summer — the season when power usage soars due to air conditioning use.

Tesla says the battery has the capacity to power 30,000 homes for up to an hour in the event of a severe blackout, but is more likely to be called into action to boost supply during peak demand periods.

The battery power packs are installed near the Outback town of Jamestown, about 200 kilometers (120 miles) north of the state capital Adelaide. They store energy generated by the neighboring Hornsdale Wind Farm, owned by French renewable energy company Neoen, to bring added reliability and stability to the state grid.

Tesla partnered with Neoen to build the battery, which is more than three times larger than the previous record-holder at Mira Loma, California.

South Australia, which relies heavily on solar and wind-generated energy, has been scrambling to find a way to bolster its fragile power grid since the entire state suffered a blackout during a storm last year. Further blackouts plagued the state over the next few months.

The battery farm is part of a 550 million Australian dollar ($420 million) plan announced in March by Weatherill to make the state independent of the nation's power grid. The cost of the battery has not been made public.

The Australian grid operator has warned of potential shortages of gas-fired electricity across southeast Australia by late next year. The shortage is looming as Australia is expected to soon overtake Qatar as the world's biggest exporter of liquid natural gas. Australia is also a major exporter of coal, which fires much of its electricity generation and makes the country one of the world's worst greenhouse gas polluters on a per capita basis.

Elon Musk's Tesla Powerwalls Have Landed in Puerto Rico

Last week, Tesla CEO Elon Musk tweeted he could help rebuild Puerto Rico's electrical grid with his company's solar panels and battery packs and Puerto Rico Governor Ricard Rossello replied in kind. 

Tesla already sent hundreds of Powerwall batteries to provide electrical stability and keep the lights on while they repair the electrical grid. Each Powerwall stores 14 Kilowatt-hours of energy, but a battery is useless without a power source, so Tesla plans to install solar panels. 

According to a photo snapped at San Juan airport Friday, Oct. 13, more Tesla Powerwalls arrived on the island. 

Tesla employees first landed in Puerto Rico a week after the hurricane, helping connect buildings with power and training locals to install their Powerwall battery packs. On September 20, ~80% of the island was without power. This is a serious issue because of the devastation left in the wake of the storm where people have lost their homes and need to communicate with each other. 

The cleaner and independent energy solution is a game-changer for any island with limited resources and geographical features that make running power lines and transporting fuel much more difficult or even impractical. Starting with centralized solar farms is a great stable start and we can expect the next steps to include smaller communities of solar cells that support each other, as illustrated in Tesla Energy video:

No Loss, No Gain

With Tesla focusing on rebuilding a great solar-powered battery storage electrical system for Puerto Rico, Elon Musk announced he had to push back the unveiling of the new Tesla Semi truck to November 16... and even fired 400+ employees. 

Anyway, looks like a brighter future for Puerto Rico and a lesson in patience and compassion for shareholders.