Florida Supreme Court gives green light to solar initiative

 

 

Two solar proposals are competing for voters' approval in Florida.

 

By Jim Saunders, The News Service of Florida

 

TALLAHASSEE — The Florida Supreme Court on October 22, 2015 approved a proposed ballot initiative that seeks to expand the use of solar energy, moving the state one step closer to a fierce political battle next year.

 

Making clear they were not offering an opinion on the merits of the proposal, justices ruled 6-1 that the initiative, backed by a group called Floridians for Solar Choice, met legal standards to go before voters. The group now will have to submit 683,149 valid petition signatures by Feb. 1 to qualify for the November 2016 ballot — about 500,000 more than it had submitted as of Thursday morning.

 

"We are thrilled with the high court's ruling so that voters may have the opportunity to vote on removing a barrier that currently blocks Florida's families and businesses from greater energy choices through the power of the free market," Tory Perfetti, chairman of Floridians for Solar Choice, said in a prepared statement immediately after the Supreme Court decision. "People power is what will get us on the ballot, and we continue to gather thousands of signatures each week from Floridians eager for solar choice."

 

The proposed constitutional amendment, in part, would allow businesses to generate and sell up to two megawatts of solar power to customers on the same or neighboring properties. In doing so, it would largely shield the solar producers from state and local regulations.

 

The initiative has drawn opposition from a coalition including major electric utilities and has spawned a competing solar ballot proposal. That proposal, spearheaded by the group Consumers for Smart Solar, is awaiting a review by the Supreme Court.

 

Dick Batchelor, co-chairman of Consumers for Smart Solar, said it was "unfortunate" that justices approved the Floridians for Solar Choice proposal.

 

"We caution Florida voters about this disingenuous solar ballot measure that favors big out-of-state solar companies instead of Florida consumers,'' Batchelor said in a prepared statement. "We simply cannot allow this seriously flawed amendment to pass. This special interest amendment puts Florida consumers, and especially our seniors, at great risk of fraud and abuse."

 

The Supreme Court reviews proposed constitutional amendments to make sure they will not be confusing or deceptive to voters. That involves making sure proposed amendments deal with single subjects and that the ballot titles and summaries — the parts seen by most voters — are clearly worded.

 

The majority opinion, supported by Chief Justice Jorge Labarga and justices Barbara Pariente, R. Fred Lewis, Peggy Quince, Charles Canady and James E.C. Perry, said the Floridians for Solar Choice proposal met the requirements.

 

"Without considering the merits of the measure, we find that the title and summary clearly and unambiguously inform the voter that the amendment will prevent government and electric utilities from imposing regulatory barriers to supplying local solar electricity up to two megawatts to customers at the same or contiguous property,'' the opinion said.

 

But Justice Ricky Polston dissented, arguing that the ballot summary is "confusing" and doesn't accurately describe the scope of the proposal.

 

In part, Polston wrote that the ballot summary "leads the voter to believe that this initiative is about someone who owns a small house or small business with a solar panel on the roof and wants to sell electricity on a small scale. However, according to the Florida Electric Cooperatives Association, a single local solar generating facility capable of generating two megawatts of electricity would span over 12 acres and could serve approximately 714 customers. The ballot summary does not provide notice to the voter that this proposed amendment provides for this scale of completely unregulated electricity generation."

 

With the court's majority approving the ballot proposal, however, the groups on both sides were clearly readying Thursday for a political fight.

 

Stephen Smith, executive director of the Southern Alliance for Clean Energy, a key supporter of Floridians for Solar Choice, quickly took aim at "big monopoly utilities" that oppose the initiative.

 

"We fully expect more misleading attacks from the big electric utilities and their proxy front groups in their desperate attempt to limit customer choice,'' Smith said in a prepared statement.

 

http://www.sun-sentinel.com/business/fl-nsf-supreme-court-solar-20151022-story.html

 

 

 

 

 

These 14 Sleek Solar Homes Do More Than Produce Power

Fewer college teams built homes to compete in this year’s Solar Decathlon, but their gee-whiz features might offer a surprising glimpse of the future.

 

Reporters view the compact, stackable home designed and built by students at New York City College of Technology on October 7, 2015, at the U.S. Department of Energy's biennial Solar Decathlon in Irvine, California.

Photograph by Thomas Kelsey, U.S. Dept. of Energy

 

By Wendy Koch, National Geographic

PUBLISHED October 09, 2015

 

They’re not simply places to live. They charge cars, grow food, collect water, and generate electricity during blackouts. These Dwell-like beauties might just make those with bigger homes a bit envious.

 

The University at Buffalo home, for example, has an indoor greenhouse for growing food year-round. Orange County’s team features a vertical garden, surf shower and—for the boomerang generation—detached studio. To withstand storms like the tornado that flattened the nearby town of Joplin, Missouri’s Crowder College and Drury University use reinforced walls surrounded by an impact-resistant fence.

 

The homes offer smart windows, accordion doors, and movable walls. Plus, they can charge a car. “We’re going to hook it up and charge it with the power of the sun,” Steve Speights, an engineering student at California State University in Sacramento, says in a video about his team’s home, complete with carport.

 

Welcome to the Solar Decathlon 2015, a biennial U.S.-sponsored contest that began Thursday in Irvine, California. Collegiate teams from around the world compete to build the most attractive, affordable, and energy-efficient home. Via solar panels, the homes produce at least as much energy as they use. Via rainwater capture, they reuse water.

 

These small homes—1,000 square feet or less—go well beyond solar technology to showcase not only smart design but also innovative ways to address drought or extreme weather. Some are engineering marvels.

 

“It’s like the biggest jigsaw puzzle you’ve even seen,” Solar Decathlon director Richard King says of Clemson University’s home, made of thousands of pieces of flat-packed plywood that lock together like LEGO.

 

Despite its wow factor, this competition has a cloudy future. It's losing competitors at a time when the U.S. solar industry is booming and other countries—China, Colombia, and United Arab Emirates—are planning similar decathlons. Six of the initial 20 teams withdrew, including Stanford, Yale, and Vanderbilt. The result: This year’s event is the smallest since the Department of Energy launched the U.S. decathlon in 2002.

ship them in pieces, and reassemble them within days at the competition.

 

For more information on the competition and videos of the homes go to:  http://news.nationalgeographic.com/energy/2015/10/151009-14-Sleek-Solar-Homes-Do-More-Than-Produce-Power/

 

Triple-filtered, recycled greywater waters at hydroponic garden at the home of Missouri University of Science and Technology on October 6, 2105, at the Solar Decathlon in Irvine, California. 

Photograph by Thomas Kelsey/U.S. Department of Energy

 

A circular window inside the home built by students at the Missouri University of Science and Technology provides a unique view of the entry by the California Polytechnic State University, San Luis Obispo, on October 5, 2015, at the U.S. Department of Energy's biennial Solar Decathlon in Irvine, California.

Photographby Thomas Kelsey, U.S. Dept. of Energy Solar Decathlon

 

 

 

 

 

Turning cow poo into power is profitable for US farm

 

• Mira Oberman, AFP

• Aug. 9, 2015

 

Plymouth (United States) (AFP) - For most farms, manure is a pungent problem. At Homestead Dairy, it smells like money.

The family-run American farm invested in a biogas recovery system which transforms cow poo and other waste into electricity. 

Enough electricity, in fact, to power 1,000 homes, a service which the local utility company pays for handsomely.

But that's just a side benefit.

Farmer Ryan Rogers checks on a generator at Homestead Dairy in Plymouth, Indiana, which invested in a biogas recovery system which transforms cow manure and other waste into enough electricity to power 1,000 homes

 

"It works economically, but one of the main reasons we did it was to try to help take care of the odor control for the neighbors," said Floyd Houin, whose family has owned the farm in Plymouth, Indiana since 1945.

"The land's important to us also because we produce a crop for feeding cows. So we want to do everything we can to take care of the land and the water. We drink the same water as everyone else."

Livestock farms typically store their effluent in open lagoons and the stench does not make them very popular with the neighbors.

The lagoons also have a significant environmental impact because they emit methane and carbon dioxide -- major contributors to climate change -- and can sully the groundwater if they leak or overflow during heavy rains.

Setting up an anaerobic digester -- essentially a giant shed that uses heat to speed up decomposition -- captures both the smell and the greenhouse gases.

 - Power one million homes -

 The Environmental Protection Agency estimates that more than three million tons of greenhouse gas emissions were eliminated last year by Homestead and the 246 other US livestock farms which have installed biogas recovery systems.

That's equivalent to taking more than 630,000 cars off the road.

There are about 8,000 dairy and hog farms in the United States which are large enough to make a biogas recovery system viable.

The EPA estimates they could generate enough electricity to power over a million homes and cut emissions by the equivalent of taking nearly four million cars off the road.

Biogas recovery is also being used to capture methane from landfills and sewage treatment plants and even at craft beer companies.

"The federal government is really committed to seeing progress in this sector," said Allison Costa, program manager for the EPA's AgStar unit.

"Widespread investment and adoption could help us make significant inroads in helping us address some of our environmental and energy challenges."

The problem is the financing, Costa said. There's a huge upfront cost and most utility companies in the United States won't pay enough for the electricity to make the project appealing to a bank loan officer.

It also requires a lot of maintenance, which many farms don't have the manpower to manage. But when it works, Costa said, it really works.

"We've seen a lot of farms expand and build a second one," she told AFP.

"You just have to have someone willing to love that digester and take care of it."

Ryan Rogers, 31, loves his digester.

"There's so many (good) things, you forget them all," said Rogers, who married into the Homestead family and spends about four hours a day on digester maintenance and management.

Controlling the smell from the 70,000 gallons of manure and urine produced every day by the dairy's 3,400 cows clearly tops the list.

Then of course, there's the crops. The digester does a much better job of turning the manure into fertilizer, which means a better yield from the farm's 4,500 acres of corn. 

Once that nutrient-rich liquid fertilizer is extracted, what's left makes for some nice soft bedding for the cows.

And instead of spending money to manage the manure, soon they'll be making money off it.

 - Recover cost in five years -

 The family managed to get a grant to help cover some of the cost of the facility and a favorable contact with the local power company which was looking to expand its renewable energy supplies.

They bring in extra income -- and fuel for the generators -- by charging restaurants and food processing plants a lower rate to dump their waste than the local landfill.

It will probably only take about five years until the initial investment is fully paid off, Rogers said. And it's working so well they're planning to build a second facility.

"It's definitely a growing field within the United States," said Mike Fenton of Michigan CAT, which sold the Caterpillar generators used by Homestead and helps them to maintain the system.

The European market is much more advanced because there are so many more subsidies available and the cost of electricity is so much higher, he said.

While US farmers may balk at the initial cost -- a system like the one at Homestead would run around $6 million -- Fenton said it's a good investment. Most farms can pay it off and start making a profit within three to five years.

"It's a proven technology that works really well," he told AFP.

Read more: http://www.businessinsider.com/afp-turning-cow-poo-into-power-is-profitable-for-us-farm-2015-8#ixzz3kUNRTWtG

 

 

 

Google’s new project could convince you to buy solar panels

 

by Napier Lopez

 

 

Google wants to make it easy for people to consider using solar power for their homes. Today it launched a tool called Project Sunroof, which uses Google Maps data to calculate your roof's solar energy potential.

 

Project Sunroof Introduction Video: https://www.youtube.com/watch?feature=player_embedded&v=_BXf_h8tEes

 

It's a simple but clever system: using high resolution satellite imagery, Google measures your rooftop area to calculate how much you could benefit from solar energy.

It'll provide an estimate for the amount of sunlight your rooftop will have available per year, taking into account shade from trees and nearby buildings, as well as roof orientation and weather. You can also input your typical electricity bills to fine tune your results.

This information is then combined to calculate how much money you could save, and Google will link you to local solar providers.

It's a clever idea that could actually entice people who might have otherwise not been interested in solar energy. Carl Elkin, Engineering Lead, says he created the project to counter people who misguidedly believe that solar energy is too expensive, or that their rooftops don't get enough sunlight.

Project Sunroof takes away the complications and makes it easy to make this assessment quickly and at your own leisure, without needing to invest hours on an expert to come in and provide a price quote. The process takes about 10 seconds.

To try out the tool for yourself, simply enter your address on the Project Sunroof website. It currently only works in the San Francisco Bay Area, Fresno and Boston, but will expand to other regions "over the coming months."

http://thenextweb.com/google/2015/08/17/googles-new-project-could-convince-you-to-buy-solar-panels/

 

 

 

 

Smart Ways to Save Around the House

Apr 6, 2015

A few quick fixes can add up to significant energy savings.

 

 

http://www.goodhousekeeping.com/home/tips/a31921/smart-eco-friendly-swaps-cree/

 

 

 

5 Hot Water Heater Options for Green Home Improvement

If you’re remodeling your home, thinking about the water heater might seem rather dull. However, this is one place where a home renovation can save you money. Here are some descriptions of energy efficient water heaters.

Gas Water Heaters: If you want to go with a traditional gas water heater, choose one that is Energy Star certified, guaranteeing the most efficient technology. They are slightly more expensive than less efficient models, but it is estimated you gain back this money in fewer than three years.

Tankless Water Heater

Tankless Water Heater: Conventional water heaters use energy 24/7 to keep your water hot, even when you’re not using it. Tankless or demand water heaters heat the water as it flows through the pipes, so it only heats what you need. This creates a substantial savings on energy costs. Demand water heaters provide hot water continuously, so you don’t have to worry about it running out. They are also quite a bit smaller than conventional tank water heaters and some can be installed outside, saving space indoors. They make an ideal home improvement project because they have a life expectancy of 20 years, far more than conventional heaters.

Heat Pump Water Heater

Heat Pump Water Heaters: A new technology, electric heat pump water heaters could save the typical family quite a bit each year when compared to a standard electric heater. They work similarly to heat pumps that are used for heating and air conditioning purposes and combine with your HVAC system. They work by drawing in warm outside air to heat the water, so they are only effective in warm climates. Homeowners can recoup the higher initial investment over time. (Most estimates are around three years.)

Gas Condensing Water Heaters: This is an even newer technology, only introduced in 2010. Using more efficient heat exchangers to capture heat from the fuel source, gas condensing water heaters can shave 30 percent off your energy bills and reduce your carbon dioxide emissions. Greater efficiency allows them to provide a continuous stream of hot water, so you don’t have to worry if you’re the last one to shower!

Solar Water Heater

Solar Water Heaters: Solar water heaters can cut your water heating bill and your carbon dioxide emissions by 50 percent compared to an electric hot water heater. This is the equivalent of not driving your car four months a year; a solar water heater’s average lifespan is 20 years, much longer than that of a traditional gas or electric water heater. Although solar water heaters take 5-10 years to pay for themselves, you can offset this cost with a federal tax credit. Enterprising do-it-yourselfers can save thousands by building their own systems.

Which water heater are you considering for your next home improvement project?

 

Joaquin Erazo, Jr. is the senior vice president of marketing and public relations at Case Design/Remodeling, Inc. Find a home remodeling company near you or read our home remodeling tips blog.

 

 

 

 

What is Light Pollution?

 

Light pollution is excessive, misdirected, or obtrusive artificial (usually outdoor) light. Too much light pollution has consequences: it washes out starlight in the night sky, interferes with astronomical research, disrupts ecosystems, has adverse health effects and wastes energy. 

 

Introduction

A little more than 100 years ago, you could walk outside at night even in a city and see the Milky Way galaxy arch across the night sky. Being able to see thousands of stars was part of everyday life, inspiring artists like Van Gogh or musical composers like Holst or writers like Shakespeare. By allowing artificial lights to wash out our starry night skies, we are losing touch with our cultural heritage (e.g., what has made us who we are). We are also losing touch with what could inspire future generations.

With more than half of the world’s population now living in cities, 3 out of every 4 people in cities have never experienced the wonderment of pristinely dark skies. How do you explain the importance of what they’ve lost to light pollution? How can you make them aware that light pollution is a concern on many fronts: safety, energy conservation, cost, health and effects on wildlife, as well as our ability to view the stars? Finally, how do you convince them that it’s worthwhile to take even small steps, to help fix this problem?

 

 

Effects of Light Pollution

In disrupting ecosystems, light pollution poses a serious threat in particular to nocturnal wildlife, having negative impacts on plant and animal physiology. It can confuse the migratory patterns of animals, alter competitive interactions of animals, change predator-prey relations, and cause physiological harm. The rhythm of life is orchestrated by the natural diurnal patterns of light and dark; so disruption to these patterns impacts the ecological dynamics.

With respect to adverse health effects, many species, especially humans, are dependent on natural body cycles called circadian rhythms and the production of melatonin, which are regulated by light and dark (e.g., day and night). If humans are exposed to light while sleeping, melatonin production can be suppressed. This can lead to sleep disorders and other health problems such as increased headaches, worker fatigue, medically defined stress, some forms of obesity due to lack of sleep and increased anxiety. And ties are being found to a couple of types of cancer. There are also effects of glare on aging eyes. (See text below.) Health effects are not only due to over-illumination or excessive exposure of light over time, but also improper spectral composition of light (e.g., certain colors of light).

With respect to energy wastage, lighting is responsible for at least one-fourth of all electricity consumption worldwide. Over illumination can constitute energy wastage, especially upward directed lighting at night. Energy wastage is also a waste in cost and carbon footprint.

The good news is that light pollution can be reduced fairly easily by shielding lights properly, by only using light when and where it is needed, by only using the amount that is needed, by using energy efficient bulbs, and by using bulbs with appropriate spectral power distributions for the task at hand.

Explore the effects of light pollution on the night sky with Light Pollution Interactive.

 

Going further… Three Main Types of Light Pollution

Clinically speaking, *three main types of light pollution include glare, light trespass and skyglow (in addition to over-illumination and clutter). Glare from unshielded lighting is a public-health hazard—especially the older you become. Glare light scattering in the eye causes loss of contrast, sometimes blinds you temporarily and leads to unsafe driving conditions, for instance. Light trespass occurs when unwanted light enters one’s property, for example, by shining unwanted light into a bedroom window of a person trying to sleep. Skyglow refers to the glow effect that can be seen over populated areas. Skyglow is the combination of all the reflected light and upward-directed (unshielded) light escaping up into the sky (and for the most part, unused). …Shielding lights significantly reduces all three of these types of light pollution.

By participating in the citizen-science campaign, Globe at Night, and taking as many measurements as you can from different locations, you will be promoting awareness and helping to monitor light pollution levels locally. The worldwide database is used to compare trends over years and with other data sets (like on animals) to see what effects light pollution has on them. Thank-you for your interest and participation in Globe at Night.  

 

The above information came from: http://www.globeatnight.org/light-pollution.php

 

For a great article on light pollution from National Geographic - http://ngm.nationalgeographic.com/2008/11/light-pollution/klinkenborg-text

 

And another - The Dangers of Light Pollution on Insect Ecosystems

 

 

San Fran's new EV chargers are solar-powered, and free!

(Hopefully this will catch on across the country!)

 

Charge Across Town is cutting carbon emissions with mobile charging. Just respect the two-hour limit.

Jim Motavalli

Apr 29, 2015

 

Charging a Chevy Volt on free electricity from one of Charge Across Town's free — and portable — solar chargers. (Photo: Charge Across Town)

The best place in the world to own an electric car is probably California, with a tie between San Francisco, San Diego and Los Angeles. Well, the city by the bay just got a big boost from something new: free solar-powered EV charging.

 

A nonprofit called Charge Across Town (CAT), looking to reduce carbon emissions in the Bay Area, has launched its “Driving on Sunshine” campaign. The plan is to increase awareness of both electric cars and solar with free electrons from three portable Envision EV ARC stations that will be strategically placed through 2015 at nine heavily trafficked locations around the city. Right now you can find them in the Mission District, at the Embarcadero, and the Stonestown Galleria Mall.

 

Carlie Guilfoile beams at the opening of the Charge Across Town free solar stations. (Photo: Charge Across Town)

 

Freeloaders will have a two-hour charging limit, says Maureen Blanc, director of Charge Across Town. She told me that CAT is “going on trust” that people will disconnect after their allotted time. Two hours on a 240-volt Level II charger should provide enough juice for 10 to 15 “e-miles,” she said. It’s hoped that four to six cars per day can charge at the stations.

 

Envision’s ARC stations cost $45,000 each, but CAT is leasing them through a grant from the 11th Hour Project. After the experiment is over in 2016, they’ll find a permanent home at the locations that got the most traffic.

 

Charge's Maureen Blanc: "You'd be surprised" how many people still don't get it in EV-heavy San Francisco. (Photo: Charge Across Town)

 

One could ask, why San Francisco? The city is not exactly starved for EV charging, or for solar installations. Awareness of both technologies would seem to be high among residents. Visit the Plugshare app here, enter the city’s name, and you’ll see dozens, if not hundreds of public stations, many of them offering free electricity, in San Francisco. Is there a need?

 

“You’d be surprised,” Blanc told me. “A lot of people are still pretty unaware. There’s still a lot of questions here about moving from fossil fuels to electric cars.”

 

Also worth noting is that PG&E, which serves central and northern California, is poised to install roughly 25,000 EV chargers in the coverage area over the next five years. The hosts won’t pay a dime for them.

 

And, of course, you can argue that San Francisco is, well, where the cars are. There are more than 60,000 plug-in cars in PG&E’s service territory, 20 percent of all those in the country, so it’s unlikely that these three new solar-powered units will sit idle.

 

The opinions expressed by MNN Bloggers and those providing comments are theirs alone, and do not reflect the opinions of MNN.com. While we have reviewed their content to make sure it complies with our Terms and Conditions, MNN is not responsible for the accuracy of any of their information.

Read more: http://www.mnn.com/green-tech/transportation/blogs/san-frans-new-ev-chargers-are-solar-powered-and-free#ixzz3ZvlwI1Nq

 

 

 

 

Tesla Home Battery is here!

This may be the future!  Prices would need to come down some and I’m sure efficiency would need to be improved.  That will happen as demand goes up!  At the end of this article, there’s a link that will take you to original blog and you can listen to a different version of the story. -- Gene

 

Tesla CEO Elon Musk Unveils Home Battery; Is $3,000 Cheap Enough?

May 01, 2015 2:05 PM ET

Bill Chappell

 

A photo released by Tesla shows its new Powerwall lithium-ion battery pack mounted on the wall (left) of a garage behind one of the company's electric cars. Tesla Energy

 

In an ambitious bid to move beyond the electric car market, Tesla has announced that it will start selling large batteries to let homeowners store electricity. The Powerwall home battery starts at $3,000.

Tesla CEO Elon Musk unveiled the new batteries Thursday night, in a move that had been both highly anticipated and the subject of much speculation. With a sleek surface and a depth of only about 7 inches, the Powerwall can be mounted on a garage wall or another surface, indoors or outside. It's roughly 4 feet high and 3 feet wide.

Explaining the company's strategy of using solar power, Musk said: "We have this handy fusion reactor in the sky, called the sun. You don't have to do anything; it just works."

The unit is geared toward homeowners who want to do any combination of three things: store backup power, minimize peak-time use of utilities' electricity and get off the commercial power grid entirely.

The Powerwall is seen as having particular allure for people who have (or want) solar panels. The large battery could supply or supplement the energy a household requires when the sun's not out.

On its Powerwall website, Tesla says:

"The average home uses more electricity in the morning and evening than during the day when solar energy is plentiful. Without a home battery, excess solar energy is often sold to the power company and purchased back in the evening. This mismatch adds demand on power plants and increases carbon emissions."

Tesla is taking orders for the batteries now, Musk says, adding that the first deliveries will be made in three to four months.

In recent days, details of the new battery venture were the subject of speculation that ranged from Tesla's reinvention of itself as an energy company to the unit's cost to homeowners.

The Powerwall's price ranges from $3,000 for a 7 kilowatt-hour model and $3,500 for the 10 kwh version. Those prices don't include an AC-to-DC power inverter or installation, but they're still far lower than the $20,000 estimate that one analyst gave to NPR's Steve Henn in the days leading up to Tesla's announcement.

For a report on Friday's Morning Edition, Steve spoke to JB Straubel, Tesla's co-founder and chief technology officer, about the batteries that the company hopes will help revolutionize the electric grid. From Steve's story:

" 'It's amazing the electric grid can work as well as it does with no storage,' Straubel says.

"Think about it. There is no way to store electricity on the grid. If there's a surge in demand and you run an energy company, you have to fire up an extra power plant.

" 'It's an entire market for energy transaction that has no inventory and no buffer,' Straubel says. 'So every single thing is delivered instantaneously, just in time.'

"And that means there is an enormous amount of waste. So Tesla wants to sell its batteries to consumers, businesses, homeowners — even utilities."

Steve also spoke to battery skeptic Robert Bryce, an author and homeowner who said that for him, the batteries would have to be very cheap.

Forbes writer Christopher Helman says that with configurations that supply either 7 kwh or 10 kwh, "the implication is that a 10 kwh system could supply 1,000 watts of current to your home for 10 hours."

But after analyzing the costs and benefits of the system, Helman adds, "If you do not have a big enough solar system to get your home entirely off the grid, then there is simply no point whatsoever in paying 30 cents per kwh to get electricity via the Powerwall."

It remains to be seen whether, for many people, Tesla's starting price of more than $3,000 will be low enough to make the economics of solar energy add up.

The BBC's Richard Taylor sees "a strong commercial rationale for Elon Musk to leverage Tesla's expertise in building highly-efficient car batteries" to put them in houses. But he adds, "The business strategy is a bit like the battery itself: high impact, but a slow release which will really only reap significant benefits over time."

 

http://www.npr.org/blogs/thetwo-way/2015/05/01/403529202/tesla-ceo-elon-musk-unveils-home-battery-is-3-000-cheap-enough?utm_source=facebook.com&utm_medium=social&utm_campaign=npr&utm_term=nprnews&utm_content=20150501