Between the Poles

Smart grid multi-vendor interoperability based on open standards and open source

The smart grid requires exchanging data between different devices from many manufacturers in the field.  Traditional utility technologies are very often vendor silos utilizing proprietary hardware, telecommunications and software platforms that communicate to a centralized hub. Last year at Distributech 2014 a group of Duke Energy and six companies called the “Coalition of the Willing” (COW) – Accenture, Alstom Grid, Ambient Corporation, Echelon, S&C, and Verizon, demonstrated interoperability between their products.  The goal was to demonstrate that data  and control commands can be shared across multiple vendor platforms (typically proprietary) to achieve interoperability with lower costs and faster response times.

At Distributech 2014 Duke energy also described  the challenges Duke has encountered in cleaning,  merging and managing operational data, combining it with other types of data including social media, and developing analytical tools to extract meaningful information.  Duke also described an innovative approach for involving vendors in the development of their smart grid platform and applications, which provided the basis for vendor involvement in COW.

COW 1 Volt/Var Optimization

The first phase of this project was to convert a Volt/Var Optimization (VVO) function to run on a distributed platform.  It used a “communications node” and a standards-based messaging architecture to enable peer-to-peer communications to integrate data from different vendors' systems.  Each of the COW participants exposed some data via a standards-based interface (Field Message Bus).  The application read two residential meter voltages supplied by Echelon meters and brought the data back via Power Line Carrier (PLC) to the Ambient communication node. If an under voltage condition was detected, the application sent a close command to the control via DNP3 through peer to peer messaging over the Verizon Wireless network. The capacitor control closed the capacitor bank to alleviate the under voltage condition on the meters.  Finally, the Alstom DMS was updated with the new state of the capacitor.

Open standards, open source

The COW 1 project involved open source hardware (Raspberry Pi), open source software and open standards.  According to Duke the Field Message Bus (FMB) is intended to be an open standard-based, common logical publish/ subscribe (pub/sub) interface that connects multiple disparate grid devices, telecom networks, and information systems. It is the key technology enabler to demonstrate the benefits of the distributed architecture by facilitating interoperability between multiple different vendor’s OT, IT, and telecom systems.  It uses open-source software to translate data to a common publish and subscribe messaging interface using the IEC Common Information Model (CIM) data model.  Other open standards that are being used in this project include industry-standard protocols as DNP3 and Modbus and messaging protocols like MQTT (for lightweight applications) and AMQP (for heavy duty messaging).

COW 2 Islandable microgrid

Last June Duke Energy announced the next phase of their interoperability project with an expanded groups of vendor partners. The second phase will include the operation of a microgrid system which will integrate distributed renewable resources such as solar PV and battery storage with a field message bus-based distributed intelligence platform with wireless communications to devices. 

The new project will support another open standard.  The Object Management Group's (OMG) Data Distribution Service (DDS) for Real-time Systems provides a secure publish-subscribe messaging protocol.  Many real-time applications involve publishing “data” which is then available to remote applications that are interested in it.  In a utility setting this communications model needs to scale to thousands of publishers and subscribers in a robust manner.

A data model based on the CIM standard will be implemented into an open field message bus to support standardized object model representations. The use case for this demonstration project will be an islandable microgrid which Duke will implement and operate at its smart grid test facility.

Duke Energy has defined a Distributed Intelligence Platform (DIP) Reference Architecture for this project.  According to Duke, the reference architecture is intended to document Duke Energy’s technology roadmap for interoperability using open standards-based distributed information systems. 

Remote microgrids expected to show strong growth in Asia Pacific

Several of the heavily populated countries in the Asia Pacific region, including Bangladesh, India, and Indonesia, are experiencing high rates of rural electrification. Meeting the increased demand for power across the region will require innovative approaches, especially for regions remote from the existing power grid.  These include microgrids that are capable of operating in isolation the centralized power grid.   For example, in Bangladesh the Globle Environment Facility (GEF) is helping to speed the rural electrification process by working with the Government of Bangladesh, the World Bank, and Bangladesh’s Infrastructure Development Company Limited (IDCOL) to increase the spread of off-grid, renewable energy technologies, such as solar home systems (SHS) in rural areas where people live too far from the main electrical grids.

India’s new government, led by Prime Minister Modi, plans to use solar power to bring electricity to the 400 million people who currently do not have access to it.  The government intends to aggressively implement the National Solar Mission that aims to install 20,000 MW of grid-connected solar power capacity and 2,000 MW of distributed solar power capacity by 2022.

A  recent Navigant Research report analyzes the Asia Pacific market for microgrids in four key segments (commercial/industrial, community/utility, campus/institutional, and remote) for nine countries (Australia, China, India, Japan, South Korea, Malaysia, Singapore, Indonesia, and the Philippines).

In emerging countries such as India, Indonesia, and Bangladesh electricity access through a centralized grid is not feasible in the immediate future for many. For example, in India many of the 400 million people who do not have access to electric power and cannot expect it in the near future because they are remote from the Indian power grid.  Microgrids, often including renewable energy sources, are a proven way to rapidly provide power to many of these people. Navigant expects that "remote microgrids" will show strong growth in emerging countries through 2023.

In addition developed nations, such as Australia, Japan, Singapore, and South Korea, will pursue technology development and pilot projects in the next few years and then will deploy diverse applications, especially in the commercial/industrial, campus/institutional, and community/utility microgrid segments. Navigant Research forecasts that annual grid-tied and remote microgrid capacity in the nine select Asia Pacific countries will grow from 37.0 MW in 2013 to 597.3 MW in 2023. The microgrid market in Asia Pacific is projected to grow from $778 million in 2014 to nearly $5.8 billion in 2023.

Integrated solar PV, demand response and energy storage in a virtual power plant enables greater consumer control

The Rocky Mountain Institute (RMI) has published a fascinating analysis of the economics of leaving the grid.  The central thesis is that solar PV and electricity storage enables consumers to leave the grid completely. 

Solar PV has already reached grid parity in about 10% of the U.S. and declining PV prices suggest that this trend will continue.  However, without the ability to store electric power, consumers with rooftop PV still require the grid for nights and cloudy days.

The development of combined solar PV and batteries from Tesla and others promises to make solar + storage accessible for increasing numbers of consumers.  These consumers could form their own microgrid, either by themselves or with their neighbours and disconnect from the grid.  Alternatively they could become a source of dispatchable power and become an energy provider.  Increasingly they could find that either of these options is economically advantageous.  This has serious implications for local utilities because if this trend develops it could seriously erode the traditional utility revenue base.   It could also lead to a completely decentralized grid comprised of many microgrids.  From an operations perspective it increases the complexity of managing the grid compared to the centralized model in use today.

Jon Wellinghof, previous chairman of FERC, thinks that the writing is on the wall and it is being driven by customers wanting more control of their energy. He said

"Advances in technology and the desire we are seeing at the consumer level to have control and the ability to know that they can ensure the reliability of their system within their home, business, microgrid or their community. People are going to continue to drive towards having these kinds of technologies available to them. And once that happens through the technologies and the entrepreneurial spirit we are seeing with these companies coming in, I just don't see how we can continue with the same model we have had for the last 100 or 150 years."

Over the past decade,distributed generation, especially solar photovoltaic (PV),  consumer demand response programs, and other flexible distributed resources of electric power has grown dramatically.  Until now, with a few exceptions such as Germany and Hawaii, distributed intermittent resources have represented a relatively small proportion of total power generation.  However, as we face the prospect of scaling the use of flexible distributed energy resources including affordable energy storage batteries, attention is focussing in many jurisdictions not only on the economics of distributed energy, but also on the control system that will balance intermittent micro-generation resources and consumer demand and the rapid evolution of new consumer devices, aka the Internet of Things.  This has led to the concept of transactive energy.

Transactive energy refers to the combination of economic and control techniques to improve grid reliability and efficiency. These techniques may also be used to optimize operations within a customer’s facility.  The Department of Energy has supported the GridWise Architecture Council in developing a conceptual framework for developing architectures, and designing solutions related to transactive energy.

A virtual power plant (VPP) is a cluster of distributed generation installations and demand response programs which are collectively run by a central control entity.  VPPs rely on existing utility grid networks to provide electricity supply and demand services for a customer. VPPs are intended to add value for both the end user and the distribution utility.  As a practical application of transactive energy concepts, virtual power plants represent a way of integrating technologies including demand response, distributed generation systems, and advanced energy storage into a network supporting sophisticated planning, scheduling, and bidding of DER-based services.

For example, RWE Deutschland AG and Siemens carried out a trial project with hydro power plants, combined heat and power units and emergency power systems. The pilot project demonstrated the technical and economic deployment feasibility of virtual power plants. Since February 2012, the electricity produced by RWE's virtual power plant is traded on the Energy Exchange (EEX) in Leipzig.

A recent report from Navigant Research forecasts that total annual virtual power plant vendor revenue will grow from $1.1 billion in 2014 to $5.3 billion in 2023.