Category: USA

Researchers accidentally make batteries last 400 times longer

rechargeable batteries

The gel surrounding the gold nanowires with manganese oxide coating protects from corrosion, allowing the battery to last 400 times more cycles. Image: Rajen Dutta /University of California Irvine

Smartphones, tablets, and most other electronics rely on rechargeable batteries, but after a few thousand uses the batteries start to lose their ability to hold a charge. The batteries of today are mainly lithium, and over time that lithium corrodes inside the battery.

Instead of lithium, researchers at UC Irvine have used gold nanowires to store electricity, and have found that their system is able to far outlast traditional lithium battery construction. The Irvine team’s system cycled through 200,000 recharges without significant corrosion or decline.

However, they don’t exactly know why. The original idea of the experiment was to make a solid-state battery: one that uses an electrolyte gel, rather than liquid, to help hold charge. Liquid batteries, like the common lithium variety, are extremely combustible and sensitive to temperature. The Irvine team was experimenting by substituting a much thicker gel.

“We started to cycle the devices, and then realized that they weren’t going to die,” said Reginald Penner, a lead author of the paper. “We don’t understand the mechanism of that yet.”

Although you may have never cracked one open (we hope), most of the batteries in your gadgets contain liquid. Liquid is used in part because its conductivity allows flexible and partial charging and discharging. Finding highly conductive electrolyte gels has proven difficult.

According to Popular Science, the Irvine battery technology uses a gold nanowire, no thicker than a bacterium, coated in manganese oxide and then protected by a layer of electrolyte gel. The gel interacts with the metal oxide coating to prevent corrosion. The longer the wire, the more surface area, and the more charge it can hold. Other researchers have been experimenting with nanowires for years, but the introduction of the protective gel separates UC Irvine’s work from other research.

“[The gel] does more than just hold the wire together. It actually seems to make the metal oxide softer and more fracture-resistant. It increases the fracture toughness of this metal oxide that is doing the charge storage,” Penner said.

While the technology promises consumer electronics that last 400 times longer, this initial test platform isn’t a true battery. Batteries have an anode, which allows electricity into the system, and a cathode, which outputs electricity. Instead of having both, the researchers linked together two cathodes that alternate charging each other. The continuous cycling from cathode to cathode makes a perfect system to test repeated recharging.

Penner says that it’s like pouring water back and forth between two cups. After a few hundred transfers from one cup to the other, some water will usually spill out, leaving less “charge.” That’s a normal battery. Penner’s system transferred the “water” between the “cups” 200,000 times, only losing about 5 percent.

Even though minuscule amounts of gold are being used in this experiment, that would still make these batteries be expensive to manufacture. Penner suggests that a more common metal, like nickel, could replace the gold if the technology catches on.

The lab’s future work will entail actually building batteries with this technology, and further investigating why the process works.

Wind and solar energy comprise 61% of 2015 capacity additions, gas contributes 35%

wind turbines USA

Wind accounted for 47% of new generation capacity, followed by natural gas (35%) and solar (14%). Image source.

In 2015, the U.S. Energy Information Administration predicted that capacity additions would begin to slow, and from 2018 to 2024 the agency believes additions will average less than 4 GW annually.

New capacity additions are slowing as efficiency and demand management techniques make new generation less necessary nationwide, and the new plants that are added are largely cleaner than in years past, SNL Energy reports.

A combination of wind, solar and natural gas made up the overwhelming majority of new capacity additions last year: Some 96%, according to SNL’s data. Coal and oil combined for less than 1%.

Those figures are similar to what EIA noted last year: that renewable power made up 70% of new generation in the first half of 2015. But SNL’s data appears to show gas additions made up some ground, ultimately consisting of more than a third of additions last year.

According to Utility Dive, in the end, gas and wind together totalled 11,848 MW of the 14,468 MW installed in the U.S. last year — 82% of the total. 2,010 MW of solar made it the third largest resource in capacity added in 2015, with 14% of the total.

Record low prices have driven a big “build cycle” for wind energy, according to a study from the Lawrence Berkeley National Laboratory. Low power purchase agreement prices and the Clean Power Plan could help spur wind’s growth in 2016, especially as the U.S. House of Representatives passed a $1.1 trillion omnibus spending bill that included extensions for the solar investment tax credit and wind’s production tax credit.

According to EIA, new power additions through 2017 will average about 17 GW annually, with about half of that being non-hydro renewable power. From 2018 to 2024 EIA estimates capacity additions will average less than 4 GW annually. That’s a large shift from the 26 GW added each year between 2000 and 2013.

MidAmerican is building the tallest concrete wind turbine tower

concrete wind turbine

MidAmerican Energy Company will include for the first time a concrete turbine tower at its new wind farm in Adams County in Iowa. Photo source.

MidAmerican Energy is planning to build the tallest land-based wind turbine in the country in Iowa.

According to todesmoinesregister.com, the Des Moines-based power company will get the added height by building the wind turbine tower from concrete instead of steel, a first for the company. The extra 100-plus feet enables the turbine to capture more wind energy, the utility said.

“Generally speaking, the higher the altitude, the greater the wind resource available,” said Mike Gehringer, MidAmerican’s vice president of renewable energy.

The 2.3-megawatt concrete tower turbine at the Adams County wind farm will measure 377 feet from ground to hub, compared to 263 feet for most of the turbines in use at other MidAmerican wind farms.

With blades extended, the turbine will reach a height of 554 feet, making it about as tall as the Washington Monument.

The utility has contracted with Siemens to supply and construct its new concrete tower design

Siemens and MidAmerican see the prototype as the model for other concrete turbine towers at future wind farms. It would open up “low-to-medium wind resource areas of Iowa for future wind development,” Gehringer said.

The company said the process of building a concrete tower is quite different from the process used to construct turbines with steel towers. “Instead of building the tower sections in a factory and transporting them to the site to be fitted together, crews pour the concrete in segments and manufacture the tower onsite,” Gehringer said.

The concrete turbine is one of 64 wind turbines planned for MidAmerican’s Adams County wind farm. Construction is underway on the 154-megawatt project, and all turbines are scheduled to be erected by the end of 2015.

Siemens sourced the concrete formwork from EFCO Corp. in Des Moines and supplied the wind turbine blades for the entire Adams project from the Siemens blade factory in Fort Madison.

Moving to renewable energy would create millions of jobs, study finds

solar industry jobs

Moving toward renewable energy would be a boon to the economy, studu says. Image source

A new report has found that transitioning to a clean energy economy would be an economic boon to the United States, increasing employment, reducing costs to consumers, and benefiting investors.

The report, from NextGen Climate America, showed that investment in efficiency, renewable sources of electricity, and fuel switching — such as moving from fossil fuel-powered cars to electric vehicles — would add a million jobs by 2030, and roughly 2 million jobs by 2050, while increasing GDP by $290 billion and improving household income. The researchers looked at scenarios that would reduce emissions by 80 percent below 1990 levels.

“While addressing climate change is one of our greatest challenges, it is one of our greatest opportunities to build the economy,” Tom Steyer, co-founder of NextGen and billionaire climate activist (and a board member of the Center for American Progress), said on a call with reporters Monday.

The construction industry, in particular, could see a huge bump in jobs — to the tune of 1.2 million more in 2050 than under the business-as-usual scenario. That’s because it will take a lot of people to build the wind farms, install the solar panels, and retrofit the buildings needed to reduce America’s dependence on fossil fuels.

Efforts to lower emissions are often subject to the criticism that they will hurt the economy, even though actual examples of programs have shown that efficiency and clean energy programs can actually boost economic factors like household disposable income.

“The go-to argument against [climate action] is that it’s bad for the economy and it’s a job killer,” Steyer said. This report shows otherwise. Steyer also pointed out that in the last few years, jobs in the solar industry have grown 20 times faster than the rest of the economy.

In addition, the so-called reference case — a general economic forecast — did not take into account the potential costs of not addressing climate change. Recent reports have shown climate change poses a significant financial risk.

According tothinkprogress.org, the report studiously stays away from telling policymakers how to get to 80 percent less emissions. Rather than policy recommendations, the researchers took a feasibility study and used it to build out the economic impacts.

The researchers used a 2014 report, Pathways to Deep Decarbonization in the United States by Energy and Environmental Economics, which looked at whether it was technologically feasible to reduce carbon emissions significantly enough to avoid 2°C warming.

Economist Jeffery Sachs told reporters it was critical to first determine where we want to go, and then tailor policies to achieve those end goals.

“Too often our national policy conversation jumps straight to the question, ‘Is it a tax? Is it this or that?’ Whereas what this report does, much better, in my opinion, is to show here’s where we want to go,” Sachs said.

Overall, the report painted an optimistic picture of the economy under a clean energy scenario. It’s worth noting, though, that the gains will not be across the board. Job growth in two of the nine regions was expected slow under the low-carbon scenarios. Those two regions — which include roughly the area from Montana to Texas, a fossil fuel heavy swath of the country — would have slower job growth.

That means that as the country does develop policies to achieve these goals, it will likely need to dedicate resources — educational and economic — to areas that will have a harder time getting off fossil fuels.

“To help them adapt we need to provide dedicated new resources for economic diversification, job creation, job training and other employment services for workers and communities affected by job losses at coal mines and coal-fired power plants,” the authors said.

Jobs notwithstanding, all regions were found to see increases in disposable income.

Moving to renewable energy would create millions of jobs, study finds

solar industry jobs

Moving toward renewable energy would be a boon to the economy, studu says. Image source

A new report has found that transitioning to a clean energy economy would be an economic boon to the United States, increasing employment, reducing costs to consumers, and benefiting investors.

The report, from NextGen Climate America, showed that investment in efficiency, renewable sources of electricity, and fuel switching — such as moving from fossil fuel-powered cars to electric vehicles — would add a million jobs by 2030, and roughly 2 million jobs by 2050, while increasing GDP by $290 billion and improving household income. The researchers looked at scenarios that would reduce emissions by 80 percent below 1990 levels.

“While addressing climate change is one of our greatest challenges, it is one of our greatest opportunities to build the economy,” Tom Steyer, co-founder of NextGen and billionaire climate activist (and a board member of the Center for American Progress), said on a call with reporters Monday.

The construction industry, in particular, could see a huge bump in jobs — to the tune of 1.2 million more in 2050 than under the business-as-usual scenario. That’s because it will take a lot of people to build the wind farms, install the solar panels, and retrofit the buildings needed to reduce America’s dependence on fossil fuels.

Efforts to lower emissions are often subject to the criticism that they will hurt the economy, even though actual examples of programs have shown that efficiency and clean energy programs can actually boost economic factors like household disposable income.

“The go-to argument against [climate action] is that it’s bad for the economy and it’s a job killer,” Steyer said. This report shows otherwise. Steyer also pointed out that in the last few years, jobs in the solar industry have grown 20 times faster than the rest of the economy.

In addition, the so-called reference case — a general economic forecast — did not take into account the potential costs of not addressing climate change. Recent reports have shown climate change poses a significant financial risk.

According tothinkprogress.org, the report studiously stays away from telling policymakers how to get to 80 percent less emissions. Rather than policy recommendations, the researchers took a feasibility study and used it to build out the economic impacts.

The researchers used a 2014 report, Pathways to Deep Decarbonization in the United States by Energy and Environmental Economics, which looked at whether it was technologically feasible to reduce carbon emissions significantly enough to avoid 2°C warming.

Economist Jeffery Sachs told reporters it was critical to first determine where we want to go, and then tailor policies to achieve those end goals.

“Too often our national policy conversation jumps straight to the question, ‘Is it a tax? Is it this or that?’ Whereas what this report does, much better, in my opinion, is to show here’s where we want to go,” Sachs said.

Overall, the report painted an optimistic picture of the economy under a clean energy scenario. It’s worth noting, though, that the gains will not be across the board. Job growth in two of the nine regions was expected slow under the low-carbon scenarios. Those two regions — which include roughly the area from Montana to Texas, a fossil fuel heavy swath of the country — would have slower job growth.

That means that as the country does develop policies to achieve these goals, it will likely need to dedicate resources — educational and economic — to areas that will have a harder time getting off fossil fuels.

“To help them adapt we need to provide dedicated new resources for economic diversification, job creation, job training and other employment services for workers and communities affected by job losses at coal mines and coal-fired power plants,” the authors said.

Jobs notwithstanding, all regions were found to see increases in disposable income.

California’s plan to gain 50% clean energy by 2030

renewable energy California

California Governor Jerry Brown has signed landmark legislation requiring the state to get 50 percent of its energy from renewables by 2030. Image via ww2.kqed.org

California’s Governor, Edmund G. Brown Jr., recently signed an legislation committing the state to generating half of its electricity from renewable sources by 2030.

According to energymatters.com, the bill, SB 350, builds on California’s current 33 percent renewables portfolio standard, which was signed into law by Governor Brown in 2011.

“California has taken groundbreaking steps to increase the efficiency of our cars, buildings and appliances and provide ever more renewable energy,” said Governor Brown. “With SB 350, we deepen our commitment.”

Now known as the Clean Energy and Pollution Reduction Act of 2015, the legislation also seeks to double the energy efficiency savings in electricity and natural gas final end uses of retail customers through energy efficiency and conservation.

The Governor had also attempted to implement legislation to enforce a 50% reduction in petroleum use by 2030, but was reportedly defeated by oil interests. California produces around 218 million barrels of crude oil and is the 3rd largest producing state in the U.S. according to the Western States Petroleum Association (WSPA).

“What has been the source of our prosperity now becomes the source of our ultimate destruction, if we don’t get off it. And that is so difficult,” Brown said at a signing ceremony at Griffith Observatory. Images captured at the signing clearly show thick haze enshrouding the city of Los Angeles.

Still, Governor Brown sees today’s signing as a major step forward. His efforts and those of Senator Kevin De Leon have been praised by various groups.

“PSR-LA is committed to continue to work with the Governor, the Legislature, and the California Air Resources Board to make sure SB 350 is fully implemented,” said Physicians for Social Responsibility-Los Angeles (PSR-LA) Executive Director Martha Dina Argüello.

“By increasing renewable energy production and energy efficiency in buildings we can reduce the terrible health burdens caused by our use of dirty energy and fuels.”

The legislation is good news for the state’s solar industry.

According to the Solar Energy Industries Association (SEIA), California installed 4,316 MW of solar electric capacity last year, ranking it 1st in the USA. The state also leads the nation in total installed capacity, with 11.535GW operational.

The SEIA says there is enough solar installed in the state to power 2,891,000 homes.
More than 2,200 solar companies are operating in California; manufacturing products and providing services ranging from solar power system installations to the manufacturing of components used in solar panels.

3D printing garbage off the planet

3d printing garbage

Transforming garbage into products with 3D printing. Photo via wagingnonviolence.org

AlphaPura is a global initiative to fund and develop 3D printers capable of repurposing the bulk of meltable human garbage on Earth into new products, and into global solutions.

The story of AlphaPura began with Frederick Janson, a former research professional at Stanford University School of Medicine, and graduate business professor, who developed a 3D printed water filter, which did not require a filter or electricity to purify water.

According to 3D Printing Progress, Janson envisioned that his product could convert the oceans, seas, and waterways of the world into drinkable water, to serve a hungry and thirsty market of no less than 2 billion people. Though Janson had developed no elaborate marketing campaign for this invention, in a single day it went viral, with thousands of people taking an interest in this global solution to the fresh water crisis and famine crisis.

The problem was that 3D printing building materials were cost prohibitive and did not allow Janson’s invention to compete with substitutes on the market, and so Janson shelved this global solution to develop a global solution to reduce the cost of 3D printing consumables, whereafter he designed the AlphaPura 3D printer, to be able to 3D print using meltable waste, effectively developing an additional global solution, that of reducing human waste materials by transforming human waste into a “free” building material. To summarize, Janson designed a way to repurpose the world’s meltable trash.

To be able to turn these ideas into reality, Janson built the first prototype for these global solutions out of an EV3 robotics set made by Lego. The first design was one that was “off the grid”, such that it could use renewable energy sources and/or non-renewable energy sources to recharge this 3D printer, so that it could be used in emergency situations.

The former design employed a programmable fresnel lens on a robotic arm and tungsten funnel-extruder combination to superheat meltable materials in a controlled manner, by employing a programmable swinging shade between the Sun and the fresnel lens in such a manner as to achieve the optimal melting temperature of most objects.

A more ambitious and future design employs a laser in addition to a fresnel lens (which is ideal for “off-the-grid” usage, but requires sunshine to be able generate energy through a steam engine and to melt materials, and thus is limited as to where it can be used, though other renewable energy technologies could be used here instead of a fresnel lens) to superheat meltable waste into the molten state required to repurpose the waste into a 3D printed object or mold.

The current design and the one currently being proposed for funding simplifies the design by removing the solar panel, external energy inputs and associated renewable energy generators, the rechargeable battery of this device, and the fresnel lens robotic arm with the shading mechanism, which would otherwise swing into the maker space as needed — features they plan to offer in an a-la-carte and customized build-your-own printer in the future, along with other novel swing-in features on robotic arms, including, but not limited to, miniature power tools, and along with different maintenance service plans, training service plans, and do-it-yourself kits, the latter of which will allow users to swap in dedicated tungsten extruder-repurposer “printer heads” for each material type they seek to repurpose, to eliminate the need for cleaning extruders between material types they are repurposing.

Tungsten Design for this Invention

As this technology seeks to repurpose the bulk of human solid waste on Earth, some of the AlphaPura 3D printer needs to be made out of an abundant and inexpensive building material with a melting temperature above that of most solid waste, and such, tungsten has been selected as the primary building material, as it has one of the highest melting temperatures on Earth, 6000+ degrees F, more than a couple of thousand degrees hotter than the temperatures being generated by a fresnel lens, on the order of 3800 degrees F, which is hotter than the melting temperature of most metals, glass, and plastics, whose range is between 150-3000 degrees F, with plastics at the lower end, glass in the middle, and metals at the higher end, with respect to melting temperatures.

The inventors believe they can build, test, and deliver a functional prototype in the next 18 months with financial support. A likely risk is that they won’t be able to configure the 3D printer software to melt down all of the different types of plastic, glass, metal, concrete, and other meltable waste within 18 months, and so are committed to releasing software updates on a continuing basis, until there is a program for every waste material that can be repurposed.

JAM IN THE VAN, the solar-powered mobile music studio

solar-powered van

JAM IN THE VAN. Photo: Abran Rubiner

JAM IN THE VAN is a solar-powered mobile music studio and discovery platform that is set to travel over 10,000 miles this year. Housed inside an RV, it greatly differs from typical music studio setups and is able to hit the road in search of music to record.

The one-of-a-kind platform was founded in 2011 by music fans Dave Bell, Jake Cotler, and Louis Peek in Venice, California. The RV was outfitted with a full HD audio/video production suite, enabling it to capture unique live music performances at festivals and other venues across the country.

According to psfk.com, over five hundred sessions have taken place inside the mobile music studio, with a mix of both emerging and already established musical acts including Gary Clark Jr., George Clinton, Matisyahu, Misterwives, Allen Stone, ZZ Ward, Robert DeLong, and The Orwells.

JAM IN THE VAN has helped introduce music fans to some great new acts, putting on shows in Los Angeles, New Orleans, Bonnaroo and SXSW. When not on the road, the bright and colorful RV hosts musicians in its hometown, and all of the performances can be seen on their official YouTube channel.

This year looks set to be a big one for the solar-powered mobile studio, which will be traveling over 10,000 miles to bring music fans more than two hundred sessions from buzzworthy bands at festivals across the U.S. They are taking over SXSW music festival in Austin, Texas this month and have partnered with GQ to showcase over forty bands at the ‘GQ x JAM IN THE VAN HOUSE’. The founders said:

“2015 will be the most prolific year to date for JAM IN THE VAN. We’ll travel more miles and discover more great music than ever before. We plan to expand our content slate and increase our reach to cover a broader fan base than ever before.”

You can get a good look at JAM IN THE VAN and see some musicians performing in the unique studio below:

Unprecedented solar power boom in U.S.

solar power in U.S.

Solar boom in U.S.

U.S. solar power grew by 6.2 gigawatts in 2014, a 30 percent increase over the previous year and representing nearly $18 billion in new investment, according to data released by the Solar Energy Industries Association and GTM Research.

According to Scientific American, the new power systems, comprising tens of thousands of photovoltaic (PV) arrays for homes, schools, businesses and utilities, as well as a handful of large concentrated solar power facilities in places like the Mojave Desert, raised the United States’ profile as one of the world’s leading adopters of solar power, officials said.

But the future for U.S. solar isn’t without its bumps.

New installations of nonresidential solar panels, while accounting for more than 1 GW of power, shrank by 6 percent year over year, a condition caused by a variety of factors “ranging from tight economics to difficulty financing small commercial installations,” GTM analysts said in their latest “U.S. Solar Market Insight Report.”

Meanwhile, the industry’s primary federal support—the 33 percent investment tax credit (ITC)—is set to expire at the end of 2016, effectively shifting the cost burden of solar fully to developers and consumers of clean power. And as with other renewable energy resources, solar’s future will be affected by the status of state renewable portfolio standards that direct rate-based utilities to produce or acquire a percentage of their power sales from clean energy resources.

Yet, even with those caveats, industry officials and analysts forecast a continued boom in U.S. solar markets over the near term, with a projected 31 percent growth target for 2015. The growth will be fueled by falling costs for solar panels and modules, business model innovation that allows for more flexibility in ownership, favorable political and regulatory environments, and increased access to low-cost capital.

Solar beats wind and coal on key metric
Shayle Kann, senior vice president at GTM Research, noted that in just five years, the U.S. PV market—which does not include concentrated solar plants—has witnessed a fourfold expansion, from an estimated $3 billion in 2009 to $13.4 billion last year.

Moreover, solar accounted for 32 percent of the nation’s new generating capacity in 2014, beating out both wind energy and coal for the second consecutive year. Only natural gas constituted a greater share of new generating capacity, according to the report.

“From a high-level national perspective, the market has continued to see really impressive growth,” both in established solar markets like California and Arizona and in regions where solar is a relative newcomer, such as in Virginia, the Carolinas, Georgia and Louisiana.

Some of the growth, especially in emerging solar states, was attributable to state incentives for residential and commercial solar, the growing popularity of third-party leases offered by firms like SolarCity and Sunrun, and a desire on the part of large utilities to diversify their fuel portfolios to include renewable energy.

Cory Honeyman, a GTM solar analyst and lead author of the 2014 market report, further noted that “2014 was the year where the concept of retail rate parity became something that extended beyond California to a growing number of other markets.”

For example, North Carolina for 2014 was the nation’s No. 2 solar state by installations behind California, with 397 megawatts of new solar power coming online. It was followed by Nevada, Massachusetts, Arizona and New Jersey, all of which have well-established solar markets.

Other states rising in the solar ranks include New Mexico, Missouri and Maryland. New Mexico for the first time became a top 10 state for solar development thanks to its 88 MW gain in solar capacity last year.

New York, Texas and Hawaii also each added more than 100 MW of solar capacity in 2014, securing their spots among the nation’s solar leaders. Elsewhere in the Southeast, Georgia and Tennessee saw marked increases in utility-scale solar, while Louisiana and South Carolina experienced sustained growth in the residential solar sector, according to GTM.

The U.S. residential sector added 1.2 GW of capacity in 2014, marking its first time surpassing 1 GW, according to GTM. Residential PV continues to be the fastest-growing market segment in the U.S. solar sector, riding three consecutive years of 50 percent or higher annual growth.

The utility sector also remains very strong, adding nearly 1 GW annually over the past several years. In 2014, 3.9 GW of utility-scale PV projects came online in the United States, with an additional 14 GW of projects under contract.

“Today the U.S. solar industry has more employees than tech giants Google, Apple, Facebook and Twitter combined,” Rhone Resch, SEIA’s president and chief executive officer, said in a statement. That success, he added, has come in part from the 9-year-old investment tax credit for solar power.

“We now have 20 gigawatts of installed solar capacity—enough to power 4 million U.S. homes—and we’re helping to reduce harmful carbon emissions by 20 million metric tons a year,” Resch said. “By any measurement, the ITC has been a huge success for both our economy and environment.”

World’s largest solar plant opens in California desert

Desert Sunlight power plant

Desert Sunlight power plant

The Southern California desert is now home to the world’s largest solar power plant.

According to the USA Today, U.S. Interior Secretary Sally Jewell joined state officials on Monday to open the 550-megawatt Desert Sunlight solar project in the town of Desert Center, Calif., near Joshua Tree National Park. Built by First Solar, the project generates enough electricity to power 160,000 average California homes.

Desert Sunlight received a federal loan of nearly $1.5 billion, and Jewell called its completion an example of the loan guarantee program’s tremendous importance.

“When you are stepping out with new technology, when you are trying something that has been untested before, a loan guarantee program from an organization like the Department of Energy is what provides you, as a lender, that certainty that you can step up and support the project,” Jewell told The Desert Sun.

Conservative lawmakers have derided the loan guarantee program, arguing that it’s wasted billions of taxpayer dollars. Critics have pointed to the program’s $535 million loan guarantee for Solyndra, a Fremont-based solar panel manufacturer that filed for bankruptcy in 2011.

But the Department of Energy reported last year that it expects to make a profit of $5 billion to $6 billion from the program. The department funded five traditional, large-scale solar farms, and Desert Sunlight marks the last of those projects to go online.

“They’re all rock-solid, money is good, living up to every kind of condition we put in the loan documents in terms of performance, in terms of commercial operation,” Peter Davidson, executive director of the Department of Energy’s loan programs office, said in an interview last week.

The loan guarantee program did more than fund five solar photovoltaic projects, Davidson added: It helped launch the large-scale solar industry. In 2009, there were no traditional solar farms in the United States larger than 100 megawatts. Now, 17 such projects have been financed, according to a Department of Energy report released Monday.

Solar panels “existed before as a technology, but that technology hadn’t been deployed at a large scale,” Davidson said. “Once we’ve done that, the government steps aside to let the private markets take over.”

Desert Sunlight employed an average of 440 people during more than three years of construction, and it now has about 15 full-time employees. Money provided by the project’s owners — as part of an agreement negotiated with Riverside County — is also being used to fund $400,000 in improvements to the community center in nearby Desert Center.

“The debate’s over — we’re going to be moving to more renewable energy,” Riverside County Supervisor John Benoit said.

Power from the plant will go to Southern California Edison and Pacific Gas & Electric Co.

Desert Sunlight is the world’s largest solar power plant, although only by a hair.

The Topaz solar project in San Luis Obispo County, Calif. — which, like Desert Sunlight, was built by Arizona-based First Solar — also has a capacity of 550 megawatts. But the desert has more abundant sunlight than San Luis Obispo County, so Desert Sunlight will actually generate more electricity than Topaz, said Georges Antoun, First Solar’s chief operating officer.

“It’s a beautiful sun here, year-round,” he said.

California as a whole has installed more renewable energy than any other state, noted David Hochschild, a member of the California Energy Commission.

“There were a lot of skeptics who actually didn’t believe that renewables could scale, that this cost reduction could happen, that we could introduce it to the grid,” Hochschild said. “They’ve been proven wrong.”

There’s little doubt that California will get more electricity from clean energy in the coming years. The state’s three major utilities are on track to meet or exceed a 33% renewable energy mandate by 2020, and Gov. Jerry Brown is calling for policymakers to increase that target to 50% by 2030.

It’s an open question, though, whether future solar projects will be anywhere near as big as Desert Sunlight.

Developers have been gravitating toward smaller solar farms, which are easier to build and usually have a smaller impact on species and ecosystems in California’s deserts. Desert Sunlight spans 3,800 acres near Joshua Tree National Park, and it faced vehement opposition from environmental activists during its permitting process.

If legislators adopt a 50% renewable energy mandate, it could incentivize massive projects like Desert Sunlight. But Antoun said he’d be surprised to see many more projects 550 megawatts or larger, in California or elsewhere.

“Can we create a bigger project? Of course,” he said. “But it all has to do with how much appetite (states) have for how much land to utilize, and to be committed for 20-25 years.”

Utilities faced with renewable energy mandates, Antoun said, will more likely turn to projects in the 100-megawatt range, located closer to energy consumers. Projects built near cities require far less transmission infrastructure, which is expensive to build and poses a host of environmental concerns.