By Nick Davis, Contributing Editor, EE
“The grid,” officially known as the U.S power grid or the U.S electrical grid, is the largest and most complicated machine ever built, and yet it’s one of the easiest to use — simply plug in a power cord or flip a switch. In other words, the grid is what delivers electricity from a power plant to your house. The grid was launched in 1882 at the Pearl Street Station in New York City by inventor Thomas Edison. The grid uses power plants of all kinds (e.g., nuclear, hydro, wind turbine, solar, coal, and natural gas), transformers, substations, and more than 200,000 miles1 of high-voltage transmission lines — that’s nearly the distance to the moon — and 5.5 million miles1 of local distribution lines.
Figure 1. The Gird. Image courtesy of EIA.gov.
The current grid uses a limited one-way interaction. That is, power flows from the power plant to the consumer. The Smart Grid, in contrast, introduces a two-way interchange where both electricity and information can be exchanged — in both directions — between the power utilities and the consumers. This growing network of communications, automation, computers, and control help make the grid more efficient, more reliable, more secure, and “greener.” The Smart Grid also allows for renewable technologies, such as wind and solar energy production and plug-in electric vehicles, to be integrated into our national electrical grid.
Figure 2. Smart Grid depiction. Image courtesy of SmartGrids.eu.
The Smart Grid also helps power and network companies to remotely anticipate and respond to problems, thereby allowing local distribution repair crews to fix power outages faster.
Speaking of power outages
Less than a week ago (as of this writing), San Francisco experienced a power outage which affected 90,000 people, including the closure of San Francisco’s downtown BART (Bay Area Rapid Transit) station during rush hour. And, you might ask, “what caused the power outage?” Was it terrorism? Nope. Was it hacking? Nope. It was caused by a failed circuit breaker at a substation, igniting insulation and causing a fire.2 Another power outage, although not too recent, is referred to as the Northeast blackout of 2003 which affected 55 million people. And its cause — unpruned foliage.
These two events clearly demonstrate how vulnerable our power grid really is, and further makes obvious the need for a Smart Grid.
In addition to the benefits of preventing power outages, or at least rectifying them faster, the smart grid also empowers consumers. Consider one example of an energy “smart” technology — the smart meter.
A smart meter is a new(er) kind of metering technology, for both gas and electricity, that can digitally send your actual energy usage to your utilities provider. This means households will no longer rely on estimated energy bills, or have to allow meter readers into their homes or yards to manually read the meters.
The smart meter also provides customers access to their near real-time data about their own energy consumption, which allows them to understand, analyze, and better manage their energy use, including the reduction of energy waste, and, therefore, reduce power plant emissions.
Figure 3. Example of a Smart meter.
Furthermore, smart meter data can help utilities better understand individual household electricity consumption behavior. “Power generators face the constant challenge of matching the amount of power produced at any given time with the demand from consumers. Excess generation is wasteful and expensive, while under generation can cause brownouts. For this reason, accurately predicting power demand hours or even days in advance is critical for the reliable and sustainable operation of the electricity grid.”4
And, like any new technology, not everyone is up to date and properly educated. In fact, some information is flat-out wrong. Below are some common myths surrounding smart meters:
Myth: Smart meters are a health threat because they communicate using wireless signals.
Truth: “RF emitted by smart meters is well below the limits set by FCC (Federal Communications Commission) and it is below levels produced by other common household devices like cell phones, baby monitors, satellite TVs, and microwaves. In fact, you would have to be exposed to the RF from a Smart Meter for 375 years to get a dose equivalent to that of one year of 15-minutes-per-day cell phone use.”3
Myth: Smart meters will not keep my data secure.
Truth: “Just as the banking, credit card and cable industries have provided secure access to your information online, the utility industry is poised to do the same using advanced security and encryption technology to safeguard your data. The privacy of your data is protected now. Utilities work constantly to safeguard it. That will not change with the use of smart meters.”3
Myth: Smart meters do not provide any consumer benefits.
Truth: “Working as a part of the smart grid, smart meters improve power outage detection and notification. smart meters electronically report the location of outages before you ever have to call your utility, making restoration faster and status notification to you much easier.” 3
From the perspective of the environment, it too will benefit from the smart grid as power demands can be smoothed while intermittent renewable energy resources, such as solar plants, wind farms, and hydroelectric dams, can be taken advantage of. More so, sophisticated smart grid sub-systems will strategically manage these diverse and geographically scattered renewable energy resources to ensure that their energy will be stored safely, in large-scale energy storage, and distributed where and when it’s needed.
It’s not all sunshine for smart grid technologies: Utilities wage campaign against rooftop solar
In 2012, the nation’s top utility executives gathered to discuss warnings about a grave new threat to operators of America’s electric grid. And what’s this “grave threat” you might ask? Rooftop solar panels.
These executives could see the signs of declining retail sales, loss of customers, and possibly becoming obsolete if the demand for residential solar continued to climb. Net metering is a billing mechanism that credits solar energy system owners for the electricity they add to the grid.5 Unfortunately, but not surprising, some utilities see net metering as a way for them to lose revenue.
Figure 4. Illustration of Net Metering. Image courtesy of The Washington Post.
As one could predict, “Utility companies are targeting the residential solar industry with proposed laws restricting ‘net metering,’ the practice that allows solar customers to earn credit for the surplus energy they produce. Industry groups say current laws give unfair advantages to solar users, while opponents say the real aim is destroying a rival business.”6
Figure 5. States fighting over home solar. Image courtesy of The Washington Post.
In fact, the officials in some states, like Florida, have ruled “off-grid” homes as being illegal since they violate the International Property Maintenance Code, which mandates that homes must be connected to an electricity grid and a running water source.7
The smart grid, with all its smart technologies, tools, and devices, will definitely have a positive impact on our national power grid in terms of efficiency, reducing emissions, and improving its robustness and security. Sure, it’s a new technology — any new technology, especially a disruptive technology, will have hurdles to overcome. However, I do think we all want a reliable, safe, and cost-effective power grid (in that order), and the promised Smart Grid is in position to deliver just that. Furthermore, I firmly believe that the smart grid, in terms of development and deployment, will be a living entity. It will constantly improve and evolve as time goes on — for generations — just as our current grid has done so since its inception in 1882.
By Nick Davis, contributing writer/electrical engineer
Nick Davis holds a Bachelor of Science degree in electrical engineering from the University of Idaho. He has worked in both small and large companies ranging from less than 50 employees to more than 30,000. During his 16 years in the engineering field he’s filled many engineering roles, including design engineer, system engineer, and test and validation engineer. His current interests include microcontrollers, entrepreneurship, and small business development.