Nav: Home

Chinese power: Challenges and R&D opportunities of smart distribution grids

October 19, 2014

After conducting an investigation about the current state of the operation of medium voltage distribution grids and the integration of distributed generation (DG) of renewable resources across China, scientists at the Key Laboratory of Smart Grid, under the auspices of the Ministry of Education, at Tianjin University in the east coast city of Tianjin, set out an array of R&D opportunities to modernize these grids.

Researchers Yu Yixin, Zeng Yuan, Liu Hong and Sun Bing state in a recent paper published on the Beijing-based journal SCIENCE CHINA Technological Sciences that it is urgent to modernize China's distribution grids, and that R&D opportunities aimed at reaching that goal should be mapped out and seized.

In their study, "Challenges and R&D opportunities of smart distribution grids in China", these researchers outline the contours of power distribution grids in terms of the practical distribution asset utilization, the simultaneity factor of feeder loading, load compositions and characteristics, along with urban reliability and the integration of distributed generations of renewable resources.

These scientists write in the new study that "the challenges to modernize the distribution grids in China are to improve the asset utilization rates, the electricity efficiencies and the reliability of distribution systems, as well as to integrate increasing amount of variable distributed renewable resources".

Smart grid is an evolving goal as a key development strategy across China, they explain. And constant research is needed to forecast fluctuating demand and to estimate changing costs and benefits.

But the smart grid can only be constructed based on the existing power system, they point out. Only through a very profound understanding of existing weaknesses of current power grids and by fully tapping their potential can the system realize maximum benefits with minimum costs. Yet research on this important point is limited at present, although scholars in China have done lots of research about smart grid and power companies have invested extensive amounts of funds and manpower on related pilot projects.

For the sustainable development of society, improving the power asset utilization rate has always been regarded as a mission with high priority in power companies of developed countries, they explained

According to statistics, the researchers noted that distribution assets involving the investment up to trillions of Chinese yuan accounted for more than half of the entire grid of China.

Among 40 Chinese cities studied, they explain, the annual average utilization rates of major 10kV equipment were below 40%, far below the comparable levels in developed countries (please see Figure 1).

The customer average interruption duration index (CAIDI) of urban 10kV users in China was 7.01 hours in 2011; during the same period this index averaged 74 minutes for urban and rural users in the U.S. The index ranged from 40 to 70 minutes in developed European countries and was less than 5 minutes in Japan and Singapore.

Yu Yixin, co-author of the paper, states that major equipment deployed across distribution grids in most Chinese cities is running with low loads, and that 10kV distribution grids are operated with a relatively large margin. But large margins ordinarily coexist with high reliability, not a low one. This is a question which needs careful consideration.

The cost of distributed generation of solar and wind power is reducing to an economically viable level, and the payback period is around 7 to 10 years. Integrating renewable energy generations into the distribution grids of load centers under an "active distribution network" mode (mode II in figure 2) is a better alternative to the centralized long-distance power transmission mode in the form of "wind power and thermal power bundling" (mode I in figure 2) for large-scale wind power in terms of minimizing the full social costs.

The U.S., some European countries and Japan have accumulated extensive experience and developed standards and protocols. However, comparable work is just beginning in China.

Professor Yu Yixin states that the current distribution grids in China should improve the economic efficiency of construction and operation urgently, especially the asset utilization rates.

Under the current system, Professor Yu explains that the reliability of power supply and the power quality cannot meet the requirement of the upcoming digital society.

At the same time there is a checkerboard of challenges to be crossed in integrating distributed generation, including renewable energy, Professor Yu adds.

Based on the above challenges, an array of R&D opportunities is listed in realizing smart distribution grids by the authors of this paper.

Efforts to seize these R&D opportunities should be aimed at the models and topologies of network infrastructure, at the communication and interconnection methods and related technologies, and at the function of self-healing and operation optimization and voltage management.

Likewise, R&D should be targeted at utilizing demand response and demand load control and improving electrical efficiency, at related laws and regulations on the power market, and at fostering smart grid investment and informing regulatory frameworks.

Meanwhile, attention associated with R&D opportunities should also be paid on flexible plug and play on EV, on standards and protocols for communication and interoperability of smart distribution grid considering DG, on comprehensive models and tools for robust operations and planning.
-end-
This research received support from the National Social Science Foundation of China (Grant No. 12&ZD208).

See the article:

Yu Y, Zeng Y, Liu H, Sun B. Challenges and R&D opportunities of smart distribution grids in China. SCIENCE CHINA Technological Science, 2014, 57(8): 1588-1593.

http://link.springer.com/article/10.1007/s11431-014-5585-2?sa_campaign=email/event/articleAuthor/onlineFirst

SCIENCE CHINA Technological Science is produced by Science China Press, a leading publisher of scientific journals in China that operates under the auspices of the Chinese Academy of Sciences. Science China Press presents to the world leading-edge advances made by Chinese scientists across a spectrum of fields.

http://www.scichina.com/english/

Science China Press

Related Wind Power Articles:

Wind forecasts power up for reliable energy production
Prediction of wind speed and direction for up to several hours in advance improves Saudi Arabia's wind energy potential.
Researchers to investigate wind power effects on bats in the Baltic Sea region
Despite the increasing numbers of wind turbines, their impacts on the environment are poorly known.
Offshore wind power now so cheap it could pay money back to consumers
The latest round of offshore wind farms to be built in the UK could reduce household energy bills by producing electricity very cheaply.
Blueprint may power up KSA's wind energy future
High-resolution analysis of wind speed across Saudi Arabia can help fast track the expansion of the Kingdom's emerging world-class wind energy industry.
New system uses wind turbines to defend the national grid from power cuts
A 'smart' system that controls the storage and release of energy from wind turbines will reduce the risk of power cuts and support the increase of wind energy use world-wide, say researchers at the University of Birmingham.
Wind beneath their wings: Albatrosses fine-tuned to wind conditions
A new study of albatrosses has found that wind plays a bigger role in their decision to take flight than previously thought, and due to their differences in body size, males and females differ in their response to wind.
Supercomputing future wind power rise
First detailed study of scenarios for how wind energy can expand to 20 percent of total US electrical supply by 2030.
Supporting structures of wind turbines contribute to wind farm blockage effect
Much about the aerodynamic effects of larger wind farms remains poorly understood.
The complicated future of offshore wind power in the US
In recent years the US Department of Energy laid out an ambitious plan to grow the US offshore wind sector.
Wind power vulnerable to climate change in India
The warming of the Indian Ocean, caused by global climate change, may be causing a slow decline in wind power potential in India, according to a new study from the Harvard John A.
More Wind Power News and Wind Power Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: The Power Of Spaces
How do spaces shape the human experience? In what ways do our rooms, homes, and buildings give us meaning and purpose? This hour, TED speakers explore the power of the spaces we make and inhabit. Guests include architect Michael Murphy, musician David Byrne, artist Es Devlin, and architect Siamak Hariri.
Now Playing: Science for the People

#576 Science Communication in Creative Places
When you think of science communication, you might think of TED talks or museum talks or video talks, or... people giving lectures. It's a lot of people talking. But there's more to sci comm than that. This week host Bethany Brookshire talks to three people who have looked at science communication in places you might not expect it. We'll speak with Mauna Dasari, a graduate student at Notre Dame, about making mammals into a March Madness match. We'll talk with Sarah Garner, director of the Pathologists Assistant Program at Tulane University School of Medicine, who takes pathology instruction out of...
Now Playing: Radiolab

What If?
There's plenty of speculation about what Donald Trump might do in the wake of the election. Would he dispute the results if he loses? Would he simply refuse to leave office, or even try to use the military to maintain control? Last summer, Rosa Brooks got together a team of experts and political operatives from both sides of the aisle to ask a slightly different question. Rather than arguing about whether he'd do those things, they dug into what exactly would happen if he did. Part war game part choose your own adventure, Rosa's Transition Integrity Project doesn't give us any predictions, and it isn't a referendum on Trump. Instead, it's a deeply illuminating stress test on our laws, our institutions, and on the commitment to democracy written into the constitution. This episode was reported by Bethel Habte, with help from Tracie Hunte, and produced by Bethel Habte. Jeremy Bloom provided original music. Support Radiolab by becoming a member today at Radiolab.org/donate.     You can read The Transition Integrity Project's report here.