Smart methods to securing supplies

Power supply systems are undergoing dramatic change. An electrical grid receives power from a variety of sources and distributes that power to different consumers. The power flowing in and out of the grid must be closely matched on a real-time, continuous basis. It is a challenge for electric utilities to provide reliable, quality power due to equipment failures, power disturbances and outages.

The closure of baseload power stations and rising future demand for power - prompted by factors such as the move to electric cars, rising summer temperatures, and cold winters - is prompting a call for new solutions to increase the resilience of the national power supply.

Energy storage makes it easier to manage large amounts of wind and solar energy on the grid, which are inherently variable in their production. But electrical energy is not stored in significant quantities, which makes it difficult for grid operators to manage peaks and valleys in supply and demand.

The internet of energy

Virtual Power Plants could decarbonise electricity supplies, while reducing demand on the electricity network by harnessing power from small clusters of combined heat and power (CHP) systems.  This could avoid the expense of building additional electrical generating capacity.

Virtual Power Plants have been described as the 'internet of energy'. They use complex software and a central control system to tap into existing distributed generation capacity - linking demand and supply - to improve the wider performance of the electricity system.

A research consortium has undertaken extensive simulation and modelling, using real data from ENER-G CHP systems and UK Power Networks' London electricity network. This has demonstrated the scale of the opportunity for tapping into existing low carbon decentralised CHP supply network to relieve peaks in electrical demand as a more cost-efficient way of increasing network capacity and performance.

"We face the twin challenges of improving power resilience, while also decarbonising supplies," said Chris Marsland, Technical Director for ENER-G Combined Power. "Simply building additional large power plants to expand the existing system is unsustainable - both environmentally and from a cost point of view.  But Active Virtual Power Plants - using clusters of highly energy efficient CHP units that communicate via a decentralised smart-grid - can provide the cost-effective answer."

This could work by allowing dense CHP clusters in urban areas to be built into a technical commercial system that would respond to pricing/demand signals from the network by exporting power. The next phase is to trial the implementation of an Active CHP Virtual Power Plant and volunteer sites are currently being sought.

Smart grids

Smart networked embedded systems, widely distributed throughout the grid, can revolutionise the way electricity is produced, consumed, and distributed, making energy cheaper, cleaner, and more abundant. As with Virtual Power Plants, this is more affordable and sustainable than building new grid infrastructure.

Smart grid technology will automatically predict and respond to shifting loads, re-routing power around obstructions, introducing distributed storage and renewable generation, and even identifying and locating faults to dispatch repair crews with the appropriate equipment.

Embedded reconfigurable instrumentation and control systems are merging with cloud-based networking, analytics, and other cutting-edge information technologies. National Instruments’ CompactRIO uses LabVIEW and reconfigurable field-programmable gate arrays (FPGAs) to perform multiple digital signal processing and control tasks in parallel and in real time. In addition, emerging network communication protocols such as IEC 61850 are being defined to ensure network interoperability and compatibility from the smart sensor to the cloud.

This is being used to improve grid efficiency in India, where NexGEN Consultancy is using LabVIEW and CompactRIO for a substation automated meter reader (AMR) with advanced power measurement capabilities. Installing distributed smart sensors is the only way to fully characterise the efficiency of the grid. The NexGEN AMR system promises to improve power distribution in India and help minimise the estimated 30% power losses in the current distribution system.

The smart grid supports multiple industry protocols, such as standard Modbus using remote terminal unit (RTU) mode, DLMS, DNP, and IEC 101. The smart grid unit can communicate using wired RS232/485, Ethernet LAN, and Internet networks or wireless GSM/SMS, GPRS/FTP, and GSM/Data.

Demand side management

With OFGEM warning that there is a one in four chance of blackouts by the winter of 2015-16, Energy Assets is rolling out its Z-LYNK demand management system to help balance the UK’s energy supply and contribute to energy security.

"What demand side management does is to provide a means of immediately addressing supply and demand imbalance by switching loads quickly,” says Alan Jones, Energy Assets’ Director of Technology and Product Development and one of the UK’s leading energy technologists. "Demand management technologies currently control the lighting systems in the City of London and heating systems in London borough blocks of flats - this is a fully deployed and proven Smart Grid. Extending this concept of load shifting to a nationwide basis could be central in balancing supply with demand.”

Such technology, if applied across the electrical supply network, could handle many millions of loads simultaneously, meaning that street lighting can be dimmed or turned off when not needed, refrigeration and heating units turned off for small periods of time and office complex interior lighting systems automatically switched off overnight.

Energy Assets has targeted the industrial and commercial sector, which is responsible for around 40% of the nation’s energy consumption. Z-LYNK enables even relatively small amounts of energy to be aggregated, enabling better management of peak demand.

Energy in the water industry

Energy plays a key role in production, transfer, distribution and treatment of water and wastewater, yet a huge amount of this energy is wasted as organisations use solutions that are poorly designed, inappropriate for their applications or old out-of-date technology.

In a water treatment plant, a massive 70% of the overall energy bill is spent on running electric motors to power pumps and blowers.

The UK water industry is subject to the Water Industry Mechanical and Electrical Specifications (WIMES), which define the requirements for mechanical and electrical equipment. WIMES guidelines enable the user the to select motors now which not only comply with the second stage of the EU Regulations, but offer increased levels of efficiency, lower running costs and reduced CO2 emissions.

WEG works with OEM pump suppliers and major water companies to help them realise energy cost savings.  The company’s W22 line of motors is WIMES compliant and is available in IE2 (High) and IE3 (Premium) efficiency classes.  The IE3 Premium Efficiency versions of the motors are available now, in standard IEC frame sizes, well in advance of the next phase of the EuP Motor Regulations due for implementation in 2015/2017.

Water supply monitoring

Acquedotto Pugliese SpA (AQP) manages Bari’s drinking water supply infrastructure, spanning a network of 21,000km, serving 330 residential areas and a total of more than four million inhabitants. This complex and intricate water supply system is based on interconnected aqueducts.

The Sinni water purification plant is equipped with six 1MW lifting pumps, four of which run continuously, each with an average flow rate of 800lit/s. The Sinni plant’s high energy consumption is due in particular to the continuous operation of the pumps required to guarantee the water can be mechanically lifted to the hydraulic distribution node, and also due to the long distances across which the water travels, through sharp differences in altitude.

AQP’s key objective is to optimise electrical energy expenditure, by improving the efficiency of its machines (motors, pumps, compressors), and this has led the utility to adopt increasingly sophisticated control, monitoring and analysis tools.

The PlantPAx platform from Rockwell Automation provides automation and control based on two higher range programmable automation controllers (PACs) in redundant configuration with hot backup, operating as master controllers, and 13 Compact PACs distributed on the two East and West lines of the plant. In effect, each of these 13 Compact PACs is responsible for controlling the sequences for each phase of the process.

Security video monitoring

The Parisian water system comprises nearly 1500 miles of underground passageways dedicated to its water and wastewater operations. In 1995, Eau de Paris installed Wonderware InTouch to provide advanced visualisation and monitoring of its vast network of water distribution pipelines. The latest Wonderware InTouch upgrade includes advanced video capabilities.

Recently a request was made to minimise the potential risks of malicious or even terrorist acts that may target the city of Paris water system. To address these potential threats, access controls using cards, intruder detectors and video surveillance cameras have been installed at vulnerable sites, with all information escalated to the supervision and surveillance central division.

"These new applications have been installed on separate PCs that are independent from those in charge of controlling the water and wastewater operations. We decided to set up a video wall where large diagrams from operator screens could be displayed, including important control parameters and video images showing any intrusion attempts,” said Frank Montiel, head of the Regulation-CTM project for the Information Systems Department of Eau de Paris.

From the start, the idea was to use the detailed (and large-dimension) block diagrams of the installations, which were created with AutoCAD. To turn this into a supervisory tool, it had to easily integrate with the Wonderware InTouch HMI. The information to be displayed from InTouch included the values of useful parameters for the control functionality, as well as other sources such as surveillance videos.

Eau de Paris worked with Basis, a systems integrator specializing in industrial IT and Wonderware applications. "The actual installation took less than a month,” said Philippe Sirgue, business manager at Basis. "It was very simple to import the AutoCAD file into InTouch using a dedicated utility proposed by Wonderware.”

Elsewhere in France, Veolia selected ARC Informatique PcVue SCADA software to monitor and control services and operations at its Super Rimiez water treatment plant near Nice, one of the largest drinking water supply sites in Europe.

The SCADA monitoring software gathers data, stores it in a central IT system and then the data is processed. PcVue directly processes the data and displays it as animations (called mimic panels) using symbols that can be instantiated (known as objects). The information gathered is converted into standard PcVue objects and then stored in databases for subsequent use in associated spread sheet tools.

For data transmission network, the TCP/IP communication protocol is used throughout the plant, and at the 26 SCADA terminals. The system is based on a virtual private network on ADSL lines and the GPRS network, with a satellite link for the main connections and RTC, GSM and SMS packet transmissions for time-stamped data stored by a secure archiving server. The network serves around 450 monitoring sites and is capable of issuing an average of 8000 remote commands and acknowledging and supervising 7000 alerts every month.