By: Bob Marcotte, University of Rochester 

In order to power entire communities with clean energy, such as solar and wind power, a reliable backup storage system is needed to provide energy when the sun isn’t shining and the wind doesn’t blow.

One possibility is to use any excess solar- and wind-based energy to charge solutions of chemicals that can subsequently be stored for use when sunshine and wind are scarce. At that time, the chemical solutions of opposite charge can be pumped across solid electrodes, thus creating an electron exchange that provides power to the electrical grid.

The key to this technology, called a redox flow battery, is finding chemicals that can not only “carry” sufficient charge, but also be stored without degrading for long periods, thereby maximizing power generation and minimizing the costs of replenishing the system.

(more…)

By: Naga Srujana Goteti, Rochester Institute of Technology; Eric Hittinger, Rochester Institute of Technology, and Eric Williams, Rochester Institute of Technology

Carbon-free energy: Is the answer blowing in the wind? Perhaps, but the wind doesn’t always blow, nor does the sun always shine. The energy generated by wind and solar power is intermittent, meaning that the generated electricity goes up and down according to the weather.

But the output from the electricity grid must be controllable to match the second-by-second changing demand from consumers. So the intermittency of wind and solar power is an operational challenge for the electricity system.

Energy storage is a widely acknowledged solution to the problem of intermittent renewables. The idea is that storage charges up when the wind is blowing, or the sun is shining, then discharges later when the energy is needed. Storage for the grid can be a chemical battery like those we use in electronic devices, but it can also take the form of pumping water up a hill to a reservoir and generating electricity when letting it flow back down, or storing and discharging compressed air in an underground cavern.

(more…)

The U.S. Department of Energy (DOE) released a report Wednesday night on electricity markets and grid reliability, stating that the decline in coal and nuclear production has not impacted grid reliability, instead the rise in a diverse energy portfolio has increased the grid’s stability.

The study, commissioned by Energy Secretary Rick Perry in April, also states that coal plant closures across the country have been due to market pressure and competition from low-priced natural gas plants, not policy changes that support renewables such as wind and solar.

(MORE: Listen to our interview with former U.S. Energy Secretary and Nobel Laureate Steven Chu.)

“America is also fortunate to have a variety of fuel sources. We need to consider how to use each effectively while recognizing our differences and unique state and regional circumstances,” Perry says in the report’s cover letter. “We must utilize the most effective combination of energy sources with an ‘all of the above’ approach to achieve long-term, reliable American energy security.”

While the report does not state that there is a current concern with grid reliability, it does warn that future problems could arise if coal and nuclear plants continue to close at the current rate. Many environmental advocates cite this as a last-ditch effort for these companies to remain relevant in the energy landscape. However, the report does go on to highlight the role of renewables in developing a diverse energy infrastructure.

(more…)

By: Joshua D. Rhodes, University of Texas at Austin; Michael E. Webber, University of Texas at Austin; Thomas Deetjen, University of Texas at Austin, and Todd Davidson, University of Texas at Austin

U.S. Secretary of Energy Rick Perry in April requested a study to assess the effect of renewable energy policies on nuclear and coal-fired power plants.

Some energy analysts responded with confusion, as the subject has been extensively studied by grid operators and the Department of Energy’s own national labs. Others were more critical, saying the intent of the review is to favor the use of nuclear and coal over renewable sources.

So, are wind and solar killing coal and nuclear? Yes, but not by themselves and not for the reasons most people think. Are wind and solar killing grid reliability? No, not where the grid’s technology and regulations have been modernized. In those places, overall grid operation has improved, not worsened.

To understand why, we need to trace the path of electrons from the wall socket back to power generators and the markets and policies that dictate that flow. As energy scholars based in Texas – the national leader in wind – we’ve seen these dynamics play out over the past decade, including when Perry was governor.

(more…)

Researchers from Oregon State university have developed the first battery that uses only hydronium ions as the charge carrier, which the team believes could yield promising results for the future of sustainable energy storage.

Particularly, the researchers are interested in the area of stationary storage. This type of energy storage primarily refers to on-grid storage to harness power from intermittent sources, such as wind or solar, for later use in general distribution. Stationary energy storage is vital for the energy landscape to transition to more renewable types of energy because it will allow the electrical grid to continue to function when the sun goes down and the wind stops blowing.

This from Oregon State University:

Hydronium, also known as H3O+, is a positively charged ion produced when a proton is added to a water molecule. Researchers in the OSU College of Science have demonstrated that hydronium ions can be reversibly stored in an electrode material consisting of perylenetetracarboxylic dianhydridem, or PTCDA.

(more…)

A new study published in the Proceedings of the National Academy of Sciences predicts that as climate change continues to accelerate average temperatures, electrical grids may be unable to meet peak energy needs by the end of the century.

The electrical grid is the central component of energy distribution and consumption. In order to upgrade this massive infrastructure to meet increasing demands, the researchers behind the study estimate nearly $180 billion would have to be invested in the U.S. grid.

This from the study:

As the electricity grid is built to endure maximum load, our findings have significant implications for the construction of costly peak generating capacity.

Read the full paper.

On top of acknowledging the correlation between increasingly hot days and higher demand for electricity (i.e. increased use of air conditioners and other cooling units), the study also acknowledges how the grid could react to this extra demand for electricity during peak hours of the day.

(more…)

Global energy demands are predicted to reach 46 terawatts by 2100. That number is a far reach from the 18 terawatts of energy currently generated around the world. According to one expert in the field, a major shift in the way we produce and consume energy is necessary in order to meet future demands.

Meng Tao, ECS member and Arizona State University professor, discussed how society could move toward meeting those demands at the PRiME 2016 meeting, where he presented his paper, “Terawatt Solar Photovoltaics: Roadblocks and Our Approaches.”

“We just cannot continue to consume fossil fuels the way we have for the last 200 years,” Tao told ECS. “We have to move from a fossil fuel infrastructure to a renewable infrastructure.”

For Tao, the world’s society cannot set on a path of “business as usual” by producing energy via coal, oil, and natural gas. And while solar energy has experienced a growth rate of nearly 45 percent in the last decade, it still only accounts for less than one percent of all electricity generated.

The shift to solar

Historically, solar technology soars when oil prices are at their highest. This is especially true during the oil embargo of the 1970s. During that time, private and public investments began to shift away from fossil fuels and toward solar and other renewable energies. That trend emerged again in the early 2000s when oil prices skyrocketed to a record-setting $140 per barrel.

“In the 1970s, the motivation to invest in solar and other forms of renewable energy was geopolitical,” Tao says. “Now, that motivation tends to focus more on the environment and sustainability.”

(more…)

While society as a whole is moving toward cleaner, more renewable energy sources, there is one key component that is typically glossed over in the energy technology conversation: energy storage.

Developments in solar and wind are critical in the battle against climate change, but without advances in energy storage, our efforts may fall short. What happens when the sun isn’t shining or the wind isn’t blowing?

The folks at Popular Science are providing a friendly analogy to explain the the importance of energy storage.

If you haven’t embraced solar energy yet, it may be about time to do so. After all, it is cheaper than grid energy in 42 of the 50 largest cities in the United States.

According to the study “Going Solar in America: Ranking Solar’s Value in America’s Largest Cities,” a fully financed solar system costs less than residential grid energy purchased in over 80 percent of the largest U.S. cities. Additionally, 9.1 million single-family homeowners live in a place where their utility bill outpaces what solar would cost.

The falling cost of solar panels and solar fuel cells is largely driven by, in part, research into new materials and developments in the sciences. Check out a few interesting reads on solar energy from the ECS Digital Library:

• “Photobioelectrochemistry: Solar Energy Conversion and Biofuel Production with Photosynthetic Catalysts” (It’s open access!)
• “The Role of Energy Levels in Semiconductor-Electrolyte Solar Cells“
• “Photoelectrolysis and In Situ Storage of Solar Energy” (Throwback to 1989!)

(more…)