Just what is the Smart Grid? What makes it smart? EngineerJobs explains the coming big thing in electricity.
From Radial Topologies to the Early Grid
In the 1920s, the idea of the power grid began to take form. Instead of a solely radial transmission network, operators began to link their transmission and distribution networks together.
The chief reasons behind this were twofold: First, linked networks could provide redundant paths for energy to travel. Second, and perhaps more important, each individual network could get by with less operating reserve. Each network didn’t have to generate power sufficient to meet the highest projected demands, and that excess generating capacity could be shared where the load was greatest.
Reliability and efficiency of the fledgling grid flowered.
In the middle of the 30s, electrical generation became a regulated public good. Networks consolidated, bought each other up, and became highly vertically integrated. This remained the status quo through the beginning of the 90s, when the industry was deregulated. No longer were generation, transmission, and distribution the sole province of any one given power system operator. Deregulation allowed utilities to compete, realize greater efficiency, and enjoy more flexibility.
Putting the Smarts in Smart Grid
Much as the internet changed media by allowing two-way information flow in real-time to replace the broadcaster/consumer model, the Smart Grid uses two-way, real-time or near real time data to flow between generation, transmission and distribution. Each node of a Smart Grid is aware of what is happening in other nodes.
Smart meters allow the rest of the network to gauge demand, thus reducing the need for wasteful levels of operating reserve. Base load generation, load-following plants, and even peaking plants can be operated far more intelligently and efficiently when they are fed accurate and timely information regarding demand – tying the whole system into a cybernetic management structure.
In addition, the bi-directional nature of Smart Grid communications enables easy and feasible selling of energy back to the grid, from home solar or other small-scale generation methods.
And that’s just the beginning.
As the Smart Grid matures, this real-time information will allow for even more efficiency at every level of the generation, transmission, and distribution network. Imagine a refrigerator that runs harder when power is cheap, or a dishwasher that can be set to run when power is at its absolute cheapest in your area. Imagine home solar panels that power your life while energy is cheap, and know when to sell their capacity when energy is dear. Beyond that, imagine a transmission network that is aware, almost instantly, when there is an outage and can route power around it with little or no operator intervention.
Indeed, imagine a world where the domino effect that triggered the blackout of 2003 could never happen.
Smart Grid Case Study: Danvers, MA
As part of the American Recovery and Reinvestment Act of 2009, Danvers, Massachusetts received nearly $8.5 million in Federal funding to build out a Smart Grid. (The total cost of this pilot deployment was $16 million.)
In addition to over twelve thousand smart meters, a number of other Smart Grid technologies were employed. A communications system for advanced metering was deployed, as was a Supervisory Control and Data Acquisition system, or SCADA. Just as AMI (Advanced Metering Infrastructure) is the nervous system of of the distribution phase, SCADA is the nerve center of transmission and generation, allowing other technologies to exchange information across the system.
With AMI and SCADA in place, the town was then able to begin to automate distribution, deploy smart relays, and bring automated capacitors (essential to power quality) online. Customers were provided with in-home displays to monitor and control energy usage, and a web portal was established to allow customers to view their energy consumption in near-real time.
The results? Improved reliability, lower line losses, and granular management of time-based rates for commercial, industrial, and residential users.
AMI alone has drastically reduced the need for boots-on-the-ground meter reading, while allowing even the most energy-efficient customers to realize measurable savings on their power bills.