BASIC KNOWLEDGE - SMART GRIDS The smart grid – what it is, and why we need it
As the demand for energy steadily increases, it can no longer be met by building more fossil fuel power stations, because of their pollution and contribution to global warming. Smart grids can mitigate the problem, with their ability to integrate renewable energy sources while optimizing their handling of all energy resources – both renewable and conventional.
What is a smart grid?
For decades, our electricity needs have been adequately met by a traditional National Grid model which is conceptually quite simple. A small number of large-scale fossil fuel - or sometimes nuclear – power stations deliver power over long distances to where it’s needed: homes, commercial and retail premises, factories, hospitals, schools, and many other environments.
However, the energy market is a highly dynamic place, with many powerful factors of change. Decarbonization, decentralization, and digitalization are leading to a radical transformation of the energy landscape. Increasing integration of power from renewable sources also poses challenges to power grids. These factors add up to a grid which is complex, with many more power generating installations, from wind farms and large-scale traditional power stations to small, privately-owned units. To manage such an entity efficiently, and benefit most from its operation, we need digital technology to measure its status in real time and exert control accordingly. In response, national grid operators around the world are applying IoT technology to the electric grid, digitally transforming it into an infrastructure now known as a smart grid.
The digital IoT technology that supports two-way communication between the utility and its customers, and the sensing along the transmission lines, makes the grid smart. Like the Internet, the smart grid will become an integrated system of controls, computers, automation, analysis, and new technologies and equipment. These technologies will work with the smart electrical grid to respond digitally to quickly changing electric demand.
Smart grid definition
A smart grid uses digital technology for two-way communications between the utility and its customers, and for sensing along the transmission lines.
The smart grid comprises controls, computers, automation, and new technologies and equipment working together, so the grid can respond digitally to quickly changing electric demand.
How does smart grid technology work?
For this newer grid model, with its numbers of distributed energy sources, to function reliably and efficiently, it must be subjected to monitoring and control. As mentioned, this can be done by treating the smart grid as a typical IoT application. Data can be collected in real time from line sensors, users, and generators, and communicated to a centralized control point that can perform analysis and control functions. This allows balancing of power loads, troubleshooting of outages, and management of distribution.
It also facilitates peak shaving, where grid operators can call upon energy supplies from users’ on-site renewable energy systems, or even batteries, to supplement their own capacity during times of high demand.
Another smart grid advantage is its self-healing properties, as control systems can detect simple problems and effect repairs without intervention. More serious infrastructure damage can be reported back to technicians in the control center, allowing for a timely repair response. To further improve reliability and uptime, the smart grid can become adaptive, with power being rerouted to go around any problem areas. This limits the area impacted by power outages, and can work down to residential levels.
To achieve these levels of responsiveness and functionality, smart grids adapt technologies already in use for other application such as manufacturing and telecommunications.
Integrated communications allow for real-time control, information, and data exchange to optimize system reliability, asset utilization, and security. Areas for improvement include substation automation, demand response, distribution automation, supervisory control and data acquisition (SCADA), energy management systems, wireless mesh networks and other technologies, power-line carrier communications, and fiber-optics.
The core duties of sensing and measurement cover evaluation of congestion and grid stability, monitoring equipment health, energy theft prevention, and control strategy support. Technologies include advanced microprocessor meters (smart meter) and meter reading equipment, wide-area monitoring systems, (typically based on online readings by distributed temperature sensing combined with real time thermal rating (RTTR) systems), electromagnetic signature measurement/analysis, time-of-use, and real-time pricing tools, advanced switches and cables, backscatter radio technology, and digital protective relays. Phasor measurement units are also used.
Distributed power flow control devices clamp onto existing transmission lines to control power flow. Transmission lines enabled with such devices support greater use of renewable energy by providing more consistent, real-time control over how that energy is routed within the smart grid. This technology enables the grid to store intermittent energy from renewables more effectively for later use.
Smart power generation using advanced components matches electricity generation with demand using multiple identical generators which can start, stop and operate efficiently at a chosen load, independently of the others, making them suitable for baseload and peaking power generation.
Matching supply and demand, called load balancing, is essential for a stable and reliable supply of electricity. Short-term deviations in the balance lead to frequency variations, and a prolonged mismatch results in blackouts. The load balancing task has become much more challenging as increasingly intermittent and variable generators such as wind turbines and solar cells are added to the grid, forcing other producers to adapt their output much more frequently than has been required in the past.
Power system automation enables rapid diagnosis of and precise solutions to specific smart grid disruptions or outages. The three technology categories for advanced control methods are distributed intelligent agents (control systems), analytical tools (software algorithms and high-speed computers), and operational applications such as SCADA, substation automation, and demand response.
Watch this short video to see, how smart grids work:
Why are smart grids essential?
Renewable energy has become effective in addressing the shortfall created by dwindling numbers of fossil fuel power stations and rising demand. The UK, for example, has been recorded as running for up to 18 days without using fossil-fueled power. It also set a new solar power record on April 20, 2020 after solar farms generated more than 9.6GW of electricity for the first time. While creating these milestones, renewable energy has the attractions of cleanliness and increasingly lower cost. However, smart grids are essential for integrating these attractive but intermittent sources into the grid, so that their power can be delivered reliably to users.
Without smart grids, energy providers would be unable to integrate renewable energy sources into existing grid infrastructures. The efficiency improvements offered by smart electrical grids are also essential for making the most of the energy resources available, whether conventional or renewable.
Yet there are further advantages of smart grids. They represent an unprecedented opportunity to move the energy industry into a new era of reliability, availability, and efficiency that will contribute to economic and environmental health.
The benefits associated with the smart grid include:
- More efficient transmission of electricity
- Quicker restoration of electricity after power disturbances
- Reduced operations and management costs for utilities, and ultimately lower power costs for consumers
- Reduced peak demand, which will also help lower electricity rates
- Increased integration of large-scale renewable energy systems
- Better integration of customer-owner power generation systems, including renewable energy systems
- Improved security
A smarter grid adds resiliency to electric power systems and better prepares them to address emergencies such as severe storms, earthquakes, large solar flares, and terrorist attacks. Because of its two-way interactive capacity, the smart grid will allow automatic rerouting when equipment fails, or outages occur. This will minimize outages and their effects.
Smart electrical grid technologies will detect and isolate power outages when they occur, containing them before they become large-scale blackouts. The new technologies will also help ensure that electricity recovery resumes quickly and strategically after an emergency—routing electricity to emergency services first, for example.
In addition, the smart grid will take greater advantage of customer-owned power generators to produce power when it is not available from utilities. By combining these "distributed generation" resources, a community could keep its health center, police department, and other utilities operating during emergencies. In addition, the smart grid is a way to address an aging energy infrastructure that needs to be upgraded or replaced. It improves energy efficiency, and brings increased awareness to consumers about the connection between electricity use and the environment. It also increases national security for energy systems—drawing on greater amounts of home-grown electricity that is more resistant to natural disasters and attack.
Importantly, the smart grid also offers benefits in the form of both information and control to consumers. Smart meters will allow them to see how much electricity they use, when they use it, and its cost. Combined with real time pricing, this allows consumers to economize by using less power when electricity is most expensive.
Cyber security challenges in smart grids
Because the smart electrical grid is predicated on online communications, it opens up new vulnerabilities to cyber-attacks – in addition to any physical threats the grid already faces. This problem is exacerbated by the sheer size of a national grid as a huge heterogeneous network.
The main vulnerabilities that must be protected are:
- Availability of uninterrupted power according to user requirements
- Integrity of communicated information
- Confidentiality of user data
These vulnerabilities can be exposed by smart grid components in several ways. Smart meters autonomously collect massive amounts of data and transmit it to the utility company, consumer, and service providers. This data includes private consumer information that might be used to infer consumers’ activities, devices being used, and times when their home is vacant.
Other contributions to smart grid vulnerability include:
Intelligent devices: A smart grid has large numbers of intelligent devices that are involved in managing both the electricity supply and network demand. These intelligent devices may act as attack entry points into the network. Additionally, the massiveness of the smart grid network (100 to 1000 times larger than the internet) makes network monitoring and management extremely difficult.
Power system lifetime: Since power systems coexist with relatively short-lived IT systems, it is inevitable that outdated equipment is still in service. This equipment might provide weak security points and will often be incompatible with the current power system devices.
Implicit trust between traditional power devices: Device-to-device communication in control systems is vulnerable to data spoofing where the state of one device affects the actions of another. For instance, a device sending a false state makes other devices behave in an unwanted way.
Different Teams’ backgrounds: Inefficient and disorganized communication between teams might lead to bad decisions and increased vulnerability.
Using Internet Protocol (IP) and commercial off-the- shelf hardware and software: Using IP standards in smart grids offer a great advantage as it provides compatibility between the various components. However, devices using IP are inherently vulnerable to many IP-based network attacks such as IP spoofing, Tear Drop, Denial of Service, and others.
More stakeholders: Having many stakeholders might give rise to insider attacks, which are very dangerous.
As well as cyber threats, physical security is also a concern: unlike the traditional power system, smart grid network includes many components, most of which are external to the utility’s premises. This increases the number of insecure physical locations and makes them vulnerable to criminal access.
These vulnerabilities can be exploited by attackers with different motives and expertise, and can cause different levels of damage to the network. Attackers could be script kiddies, elite hackers, terrorists, employees, competitors, or customers. They can be classified as:
- Non-malicious attackers who view the security and operation of the system as a puzzle to be cracked. Those attackers are normally driven by intellectual challenge and curiosity.
- Consumers driven by vengeance and vindictiveness towards other consumers, motivating them to discover ways to shut down their homes’ power.
- Terrorists who view the smart grid as an attractive target as it affects millions of people, making the terrorists’ cause more visible.
- Employees disgruntled with the utility.
- Customers or ill-trained employees causing unintentional errors.
- Competitors attacking each other for financial gain.
These bad actors can cause a wide variety of attacks, classified into three main categories: component-wise, protocol-wise, and topology-wise.
Component-wise attacks target field components; these include the Remote Terminal Units (RTUs) traditionally used by engineers to remotely configure and troubleshoot the smart grid devices. This remote access feature can be subject to an attack that enables malicious users to take control over the devices and issue faulty states such as shutting down the devices.
Protocol-wise attacks target the communication protocol itself using methods such as reverse engineering and false data injections.
Topology-wise attacks target the topology of the smart grid by launching a Denial-of-Service (DoS) attack that prevents operators from having a full view of the power system, causing inappropriate decision making.
Many other types of attack, such as eavesdropping and traffic analysis, where an adversary can obtain sensitive information by monitoring network traffic, have also been identified.
A paper titled ‘Smart grid security: Threats, vulnerabilities and solutions ’ published by the International Journal of Smart Grid and Clean Energy describes these threats more fully, while offering a possible set of solutions.
The future of smart grids
Smart grids can be the link that connects organizations and individuals with the benefits of renewable energy and IoT technology. Their ability to deliver on this promise, though, depends on whether they receive sufficient investment to handle the expected increase in electrical capacity demand – although the level of investment needed is often a matter of opinion.
In the UK, for example, as part of the government’s net-zero drive, and with a looming 2030 ban on the sale of new petrol and diesel cars, up to 30 million electric vehicle chargers will need to be installed by 2050, according to the trade association for energy infrastructure companies, BEAMA. On top of that, the association says 20 million heat pumps will also be required, increasing electricity demand by more than 70 %.
BEAMA’s report found that without £330bn of investment into the grid by 2050, “the prospect of electric vehicles not being charged, heat pumps not having sufficient power, or renewable generation not connecting are real possibilities”.
Yet the government, amid a cost-of-living crisis, said the figures “overestimate the level of investment needed in electricity distribution infrastructure”.
Smart grid product and service providers, not surprisingly, take a more unreservedly positive view of smart grids’ advantages and future. Huawei, for example, believes that in the next ten years, many of the trends we see today will be more mature. Digital transformation will produce higher-quality data based on better connectivity and increased computing power. The design, planning, transmission, distribution, and use of wind and solar solutions will be vastly more efficient. The cost of solar PV will drop by a predicted 40 % over the next decade, and the use of graphene in solar PV cells will increase performance, with a predicted increase of efficiency of up to 18 %. By 2025 solar PVs are likely to be the cheapest energy source in many places.
The number of buildings that produce more energy than they consume will become mainstream, especially as initiatives like HouseZero by The Harvard Center for Green Buildings and Cities (CGBC) gather in momentum. Smart design, green materials, and solar power will work with ICT systems to maximize efficiency. Smart metering alongside electric vehicles, fuel cells, and smart appliances and devices where users can flexibly configure power use will generate more energy than is consumed, and allow users to potentially sell excess electricity to power companies. Increasingly managed by software, grids will start to manage themselves, for example, by self-adjusting to reduce losses, respond to voltage variations, and self-optimize to avoid electricity disturbances.
With the ability to source, see, and control how much electricity they use thanks to digital technology, consumers will have much more control over their energy habits. In the energy sector, digital transformation is also a customer-first journey.