China's Energy Internet

Photo: Jeremy Rifkin

Interest in the energy Internet is growing in China. Following the release of some big reforms, China is moving towards a next-generation grid -- which holds promise for those in energy storage. Here we're looking at the basics of the energy Internet, and discuss what role energy storage has to play.

What is the Energy Internet?

The Third Industrial Revolution, written by Jeremy Rifkin, presents a vision of the energy Internet. He envisions a shared, two-way energy and information network that integrates the electrical grid with natural gas, thermal power, and transportation networks via information communication technology. It relies primarily on renewable energy, and includes distributed elements, information components, and energy storage devices.

1. Energy networks are the physical foundation of the energy Internet. The electrical grid is the heart of the system. It closely integrates thermal, gas, oil, and transportation systems via electricity storage, thermal storage, and hydrogen storage technologies, as well as via vehicle charging points. High penetrations of distribution resources including distributed generation and storage helps to “flatten” the current top-down energy structure.
2. Information networks are the nervous system of the energy Internet. Most elements in the energy grid, including generation units, consumers, and T&D substations can be structured as nodes in an information network. This allows operators to collect and analyze grid information such as energy production, usage, demand, and operating status. This helps manage resources on the energy Internet.
3. Energy management, analysis, and trading platforms within the information network are used to dispatch local or regional energy resources and make the most out of the system. These platforms include big data analysis software, interactive exchange platforms, electric vehicle charging services, demand response platforms, etc.

China's Energy Internet

Research on the energy Internet in China is still in its early stages. According to information leaked from the NEA’s upcoming Energy Internet Action Plan, the energy Internet should rely on real-time, high-speed, two-way information exchange. It should use the electric grid as the core of the system, with a high degree of integration between multiple energy sources and transportation/logistics networks.

In 2014, President Xi Jinping called for an energy consumption revolution, including reduced energy consumption through industrial restructuring, implementation of energy savings guidelines, and the establishment of an energy saving mentality across society. With this in mind, we expect that China's first steps towards integrating energy resources and the Internet are most likely to involve distributed resources, microgrids, demand-side management, contracted resource management, and data-based energy services.

Energy Storage in the Energy Internet

In the energy Internet, energy storage not only includes electrical storage, but also hydrogen, heat, and natural gas storage.

The energy Internet will bring fundamental changes to every link in the energy chain, including production, transmission, and usage. As the "electricity consumption revolution" rolls onward, and continued reforms are made to China's power sector, we expect opportunities for energy storage in demand response, distributed generation, and microgrids.

Demand response in particular seems to be featured in the consumption revolution. It is also highlighted in the NEA's Energy Internet Action Plan. This is good news for energy storage, which can help reduce peak load without affecting consumer energy use.

Earlier this year, in fact, the Beijing municipal government authorized CNESA to operate the city's first integration pilot program. CNESA is helping businesses across the city save money using a custom-built online platform. We hope these experiences will inform future deployments across the country.

The new power sector reforms are also an important development. The reforms are opening up electricity retail, unlocking the potential for more distributed generation and microgrids in China. On 22 July 2015, the NEA followed up with  a document further specifying the role of microgrids in opening up electricity retail and distribution to society at large, titled Guidelines on Promoting the Construction of New Energy Microgrid Demonstration Projects. In line with the principles of an energy Internet, it encourages the use of internet-based and information technologies in generation and usage.

Although many of the precepts of a true energy Internet may be years away, China's policymakers are beginning to recognize the value that these ideas and technologies have. The confluence of power sector reforms and favorable regulations for distributed generation and microgrids suggest that non-hydro energy storage may soon be ready for its China debut.

Energy Storage in Distributed Generation and Microgrids in China

Nanji Island, Zhejiang, home of a two-megawatt lithium-ion battery supported microgrid.

According to the CNESA database, half of energy storage deployments in China are applied in distributed generation and microgrids, making these applications the most common application of energy storage technology in China.

Within this, industrial and commercial use is greatest, followed by applications in remote and island communities, accounting for 54% and 39% respectively.

There are three reasons that applications in microgrids and distributed generation have become so popular.

1. Solar PV deployments in China are moving away from purely large-scale ground-based solar farms to a mix of large-scale deployments and distributed generation.
2. For isolated and island communities, renewable generation is becoming economically competitive when compared to the costs of burning diesel or building out transmission lines.
3. In the context of a growing interest in an “internet of energy,” results from demonstration projects shifted attention towards microgrids and distributed generation.

View fullsize

       Source: CNESA

However, there are problems preventing the wider deployment of energy storage in this sector. In CNESA’s annual conference held in June, Energy Storage China 2015, experts discussed what is holding the industry back:

• Pricing – The price of residential-use electricity is too low. Demand charges are also not widespread, and where they exist, the difference isn’t big enough to support energy storage installation.
• Incentives – There are currently no subsidy programs specifically for energy storage technology. With feed-in tariffs for solar PV set at 0.42CNY/kWh (US$0.07/kWh), interest in installing energy storage to complement solar PV has been minimal.
• Management – Energy management systems for industrial installations are complex, which is hampering the expansion of rooftop PV and accompanying storage systems.
• Overlap – In some isolated communities where microgrids were built, grid companies built out transmission lines anyway, making the original microgrid installations largely extraneous.
• Technology – Technical problems have plagued existing demonstration projects, including inconsistencies resulting in diminished recharge capacity among lithium batteries, imprecise BMS systems, and a lack of technical and testing standards for PCS equipment resulting in long maintenance downtime.

Despite all this, the consensus is that distributed generation and microgrids are still going to take leading roles in commercializing energy storage in the near future. 

Promoting Electric Vehicles in Beijing

Beijing is putting out policies to get more EVs on the road.

As one of the first cities in China to promote electric vehicle use, Beijing has been at the forefront of efforts to increase the number of EVs on the road. EV use in Beijing is now moving from a pilot phase towards broader commercial development. During our annual conference last month – Energy Storage China 2015 – Director Chen Chu of the Beijing Electric Vehicle Development Center described the state of affairs for electric vehicles in the capital. Here are some of his observations and our own analysis.

Beijing EV Policies

Broadly speaking, the Beijing municipal government is focusing its attention on all-electric vehicles and the creation of an effective industrial chain. Director Chen emphasized the importance placed on promoting R&D and manufacturing, demonstration projects, and building up EV infrastructure to create a supporting framework for the industry.

In terms of policy, the municipal government has passed nearly a dozen regulations, procedures, and notices related to EVs and infrastructure since 2014. Most notable were policies related to EV purchasing and measures to establish an EV policy framework. In 2015, we’ve seen new policies come out governing new applications for EV technology and extending EV infrastructure.

Date	Policy
February 2014	Beijing Municipal Procedures for Management of Electric Passenger Car Demonstration Projects
February 2014	Beijing Municipal Regulations on EV Manufacturers and Product Auditing for  Electric Passenger Car Demonstration Projects
March 2014	Beijing Municipal Regulations on Financial Subsidies for Electric Passenger Car Demonstration Projects
June 2014	Beijing Municipal Regulations on Construction of Private Charging Infrastructure for Electric Passenger Car Demonstration Projects
June 2014	Notice on Promoting the Installation of Private EV Charging Infrastructure in Existing Residential Complexes
July 2014	Notice on Promoting the Installation of Private EV Charging Infrastructure in Property Management Areas
July 2014	Beijing Municipal EV Promotion Action Plan (2014-2017)
March 2015	Notice on Financial Policies for the Purchasing of Electric Vehicles
March 2015	Notice on Incentives for Early Retirement or Upgrading of Taxis
April 2015	Notice on Questions Regarding Beijing EV Charging Station Service Fees
May 2015	Notice on Exemption of Electric Passenger Cars from Working Day Rush Hour Road Space Limitations

Three policy documents published in 2015 are particularly interesting:

• The “Opinions on the Beijing Municipal Public Facilities Deployment Index,” a document that, among other things, specifies the allocation of parking spaces in publically-owned buildings, also included a clause reserving 18% of parking spaces in residential complexes for electric vehicles.
• The “Notice on Exemption of Electric Passenger Cars from Working Day Rush Hour Road Space Limitations,” published in May, exempted small passenger EVs from rules that restrict the number of passenger cars on Beijing’s streets during the week.
• The “Notice on Questions Regarding Beijing EV Charging Station Service Fees,” passed in April, allows operators of public EV charging stations to charge users a service fee. This fee is based on the price of gasoline, and is designed to incentivize the build-out of future charging stations. Specifically, the document specifies that the service fee cannot exceed 15% of the price of one liter of 92-octane gasoline per kilowatt-hour charged.

Collectively, these policies clarify the rules on EV infrastructure, traffic management methods, and EV charging services.  They reaffirm the city’s commitment to supporting EV development and the promotion of EVs in the consumer market.

EV Support Platforms

The city has also designed a number of software platforms to promote the expansion of the city’s EV fleet.

One such platform monitors and collects information on the battery power, vehicle status, and the geographic location of public-use electric vehicles.

Another, the Beijing EV Charging Facility Smart Management Platform, provides internet access to electric vehicles, thus giving drivers access to the current status and location of charging facilities. The platform also helps drivers navigate to charging stations and reserve a charging space in advance.

The National EV Testing Service Platform, one other such service, tests the performance of an EV and its components, including a vehicle’s drive and control systems, battery, and charging capacity.

EV Development Strategy

The city is currently working to build a hierarchical public transportation system. This includes promoting EVs for use as taxis, in delivery services, and in hourly car rentals. In terms of infrastructure, the city government has described its strategy as emphasizing slow charging for private vehicles and fast charging for public transportation.

The city is also actively exploring home charging, distributed charging stations, and park and ride charging stations at rail stations.

The Beijing city government’s active stance on EV policy suggests that the industry is picking up speed. It also show that EVs are a part of the city’s strategy to fight air pollution.

CNESA will continue to follow these developments.

Applications of Graphene in Lithium-ion Batteries

Since the announcement of the 2010 Nobel Prize in physics, graphene has received considerable attention from researchers worldwide. In 2004, Dr. Andre Geim at the University of Manchester successfully used micromechanical techniques to isolate single sheets of graphene from highly ordered pyrolytic graphene. Graphene’s unique properties have made it a highly attractive topic of research.

What is graphene, anyway?

Graphene is a hexagonal, two-dimensional allotrope of carbon. It can be formed into zero-dimensional fullerines, one-dimensional carbon nanotubes, and stacked to form three-dimensional graphite. As such, graphene is a basic component for other graphite materials. Graphene possesses many special properties. It has a tensile strength of 130GPa, 100 times stronger than steel. Its thermal conductivity is 500W·m-1K-1, three times that of diamond. Its electron mobility is 15000cm2·V-1s-1, over ten times greater than commercial silicon. At 2630m2·g-1, it has an extremely high specific surface area. It is conductive at room temperature, and functions much more quickly than present-day conductors.

Graphine itself is only one carbon atom wide. It is theorized to have a large specific surface area, high conductivity, and a honeycomb-like structure,  which is what gives it potential for use in lithium-ion batteries. The proposed applications include direct use as an anode; use in tin-based, silicon-based, or transition metal anode composites; use as a composite in lithium iron phosphate cathodes; or use as a conductive additive.

(1)   Use of graphene as an anode in lithium-ion batteries

Because graphene is composed of a single atomic layer of carbon, lithium ions can be placed between two layers of graphene to create Li2C6, a superior electrode material (with an energy density of 744mAh·g-1) compared to traditional carbon anodes. The lithium ions are stored in the spaces between the graphene sheets. It is this morphology and structure that determine the effectiveness of graphene as an anode material.

Because pure graphene has a low coulombic efficiency, a high charge-discharge platform, and low cycle stability, graphene in itself is unlikely to replace existing carbon-based commercial materials currently used in lithium-ion battery anodes. Moreover, graphene sheets stacked together lose the advantage of a large surface area to store lithium ions. However, graphene makes an excellent composite material for electrodes.

(2)   Graphene-composite anodes

Graphene is highly conductive, demonstrates high mechanical strength, flexibility, and stability, and possesses a high specific surface area. In particular, chemically transformed graphene has a high number of functional groups, making it useful as a substrate for composite electrodes.

Graphene composites with tin, silicon, and transition metals have already been researched in depth. Tin and silicon-based electrodes, when doped with graphene, can maximize synergies between the two materials. Graphene can reduce the size of the active material, prevent the agglomeration of nanoparticles, improve electrical and ionic transmission, and improve mechanical stability. These improvements lead to better capacity and rate performance, as well as longer lifecycles.

The preparation of graphene-composite electrode materials requires the uniform distribution of nanoparticles on one or multiple layers of graphene. The effectiveness of the composite is determined by the interaction between the two materials.  Presently, graphene composite manufacturing is developing to a stage where the morphology of composites can be well-controlled through in-situ and interfacial reactions. Nonetheless, easier and more effective preparation methods are crucial for the future application of graphene in lithium-ion batteries.

(3)   Applications of graphene as cathode material

Conductivity of cathodes is a major limit to the effectiveness of a battery. Many cathode materials – particularly in cases of large electrical discharge – demonstrate lower capacity than should theoretically be the case. As a result, researchers hope that graphene’s unique surface area and conductive properties will improve the conductivity of cathode materials and increase lithium ion transmission.  Adding graphene into the cathode mix reduces interfacial resistance between the electrolyte and active cathode material, and improves Li+ transmission. At the same time, graphene placed on the surface of the cathode prevents metal oxides from dissolving or transforming, thereby maintaining structural stability.

Graphene is used most commonly with lithium iron phosphate cathodes. In these composites, graphene functions as a current collector coating and conductive additive. Graphene’s two-dimensional conductive surface provides a highly active and conductive electrode, thereby improving the battery’s conductivity and rate performance.

(4)   Graphene as a conductive additive

In order to improve conductivity, conductive additives such as graphite, acetylene black, and Super P are added to battery electrodes. As a carbon material, graphene is also very effective as a conductive additive for lithium-ion batteries.

On carbon-based anodes, graphene provides more consistent conductivity throughout many discharge cycles regardless of the presence of active substances which would otherwise interrupt conduction, as compared to acetylene black. This allows for better cycling and rate performance.

On lithium iron phosphate cathodes, Super P uses small particles to fill gaps in the cathode, thereby improving conductivity. By comparison, graphene’s flexible surfaces achieve greater conductivity with fewer materials.

The biggest barrier to adoption of graphene conductive additives is that its high-rate performance is yet lacking. Current research has been limited to improving cycling and capacity under low rate conditions.

Summary

Since graphene was first isolated, it has shown usefulness in many applications –electrochemical batteries, optoelectronics, catalysts, and more. There is further potential for applications in hydrogen storage, supercapacitors, lithium-sulfur batteries, lithium-air batteries, and other technologies. Looking forward, graphene will benefit from increasing scale, lower costs, better manufacturing methods, and improved functionality. CNESA is keeping a close eye on further developments and future applications for graphene.

Demand Response in China

In April 2015, following the Power Reform Policy No. 9,  NDRC released Notice on Improving Demand Side Management Pilots through Emergency Power Mechanisms, continuing to strengthen emphasis on demand side management and demand response. This article will analyze the status of demand response and its prospects in China.

Demand Response (DR) Overview

In 2012, FERC (Federal Energy Regulatory Commission) defined demand response as follows: Changes in electric usage by demand-side resources from their normal consumption patterns in response to changes in the price of electricity over time, or to incentive payments designed to induce lower electricity use at times of high wholesale market prices or when system reliability is jeopardized.

Demand response must be distinguished from demand side management (DSM). DSM refers to when the government, through policy measures, pricing mechanisms, and other measures to guide the users and change electricity usage behavior, thus lowering peak usage, improving the efficiency of the power supply, and optimizing other electricity usage aspects. DSM includes energy efficiency, permanent load reduction, and incentives for temporary load reduction. DR is a type of DSM, as shown in the figure below.

DSM Implementation Methods

The US has some of the best developed DR, and will thus be taken as an example in introducing DSM implementation methods. In the US market, DR is mainly divided into price-based DR and incentive-based DR.

Price-based DR resources are generally from residential users whose participation is completely voluntarily and thus cannot be dispatched. As it cannot be dispatched, it is difficult for the grid to accurately determine DR capacity. But as smart metering has popularized, this type of DR resource has shown new developments. With dispersed users aggregated as one, and with the allocation of ES devices, this creates an aggregate dispatchable resource which can via contracted electricity prices or other logical price signals giving direction and paying returns.

Incentive-based DR resources are generally commercial and industrial users, and can be publically transacted on electricity markets. Grid dispatchers can arrange electricity usage plans with participants in advance, and can be thusly dispatched. This type of DR resource will generally have an ES device such as a battery, thermal storage, or ice storage air conditioning.

In the above basic DR implementation measures, each power company in the US has its own particulars, equipment, and provide a great many DR projects for users to choose from to participate in. PG&E has programs for small business DR: smart air conditioning, and business and residential interconnection projects; and programs for large to medium businesses: business incentive programs, aggregate party programs, and subsidy programs.

DR in China’s electricity market

In November 2010, China's NDRC released the <Demand Side Management Methods>, formally beginning China's DSM efforts. Following, the government released related policies, such as 2011's Guidelines on Industrial Zone Demand Side Management, 2012's Interim Methods For Demand Side Management City Pilot Project Central Financial Incentive Fund Management, and 2015's Notice on Improving Demand Side Management Pilots through Emergency Power Mechanisms, promoting the development of DSM efforts.

The above documents differentiate between DSM-type permanent load reductions and temporary DR and differentiate set incentive mechanisms, but up to now, DSM has mainly been carried out via administrative means, load control devices, and energy efficiency, with non-ideal results. Meanwhile, pricing and other market mechanisms for directing users in voluntary participation DR have had quite limited development due to greatly limited peak pricing and subsidy incentive mechanisms.

 (Note: Price compensation mechanisms for DSM facilities: Energy efficient power plants and peak shifting/peak shaving technology and other permanent load reductions: 440 CNY/kWh in east China, 550 CNY/kWh in central and west China. Demand Response temporary peak load reductions: 100 CNY/kWh.)

Background of China’s DR electricity market

Although DR is very limited in China's electricity market, its importance is already taking shape in China's energy strategy and the new round of electricity reforms. Beijing, Shanghai, and other DSM pilot cities have been testing DR projects since 2014. The data shows that DR will gain great development space in China.

•        More reasonable, improved peak pricing mechanisms will incentivize DR development

The newest policy published this April, makes a call "to incentivize active user participation in peak [super peak] load usage reduction and voluntary participation in DR, improved peak pricing and seasonal pricing can be set... to be set and implemented before the end of June 2015." The coverage scope and regional use of peak pricing will expand, and price-type DR will gain more incentives.

•        Electric service company participation, strengthening an active market

Allowing more types of retail entities to enter the end user retail market is one of the new reforms. For DR, last April's Notice also states that it will "incentivize and support the development of electric service companies, attracting the participation of top national and even global electric service companies in pilot projects."  As the market opens, participating entities and competition will increase. This could result in the emergence of more innovative projects and products, driving DR development.

However, China's present DR market still has many barriers. Participation by grid companies is very low, grid operation data is still held closely by grid companies, and there is a lack of public channels. For non-grid companies, providing DR lacks the data for economic operation analysis. For users, as they lack real-time electricity usage data analysis, it is very difficult to build enthusiasm for DR participation.

CNESA acts as a primary integrated unit of the Beijing NDRC, actively participating in Beijing's DR pilot efforts, and is currently managing the establishment of a DR management platform, which will organize under certain conditions the participation of user groups in DR in the NDRC's pilot projects. CNESA hopes to advance the continued improvement of related policies through the efforts and coordination of many parties, creating even more space for energy storage to develop.