City of Radford 1-megawatt hydropower plant at Little River Dam
The key to the geography of electricity is that the power is portable. It can be moved from the generating source, through transmission lines, to the customer. It's hard to store electricity in bulk (other than in small batteries for cars and flashlights), but we've figured out how to move it from generators to customers.
In a classic business contest a century ago, George Westinghouse and Thomas Edison built competing transmission systems for alternating current (AC) vs. direct current (DC). The physics of electricity, as documented by Nicholas Tesla, favored Westinghouse's system for transmitting AC at high voltage. Edison's DC alternative would have required building generating stations every 5 or so miles, while AC at high voltage can be transmitted for hundreds of miles with less than 10% of the power lost to resistance in the wires.
Almost all Virginia electricity is generated at a few centralized locations, typically power plants fueled by coal, hydropower, or nuclear energy. The energy is then transmitted through a grid of wires to a larger number of homes, factories, offices, etc. across the state.
The voltage of the electricity produced generators spinning at power plants is "stepped up" before being shipped out to customers as alternating current in 60-cycle phases, then "stepped down" at substations and ultimately transformers near our houses/stores/offices to become 220-volt or 110-volt circuits. (Electrons do not move down the wires in one continuous flow directly from generators to houses. Waves of AC current shift directions based on the spinning of the generators, and electrons flow back and forth a short distance through our motors and light bulbs.)
Until recently, the grid was exposed as overhead wires attached to poles and towers. That network is unsightly, so in many modern subdivisions the "last mile" of wires between substations and houses have been buried underground. The cost to bury the grid is relatively high, but buried wires are not disrupted by trees or ice storms. The cost to bury high-voltage transmission lines is dramatically higher, so they have been placed underground in only a few places, starting with a 0.4 mile stretch in Arlington County.
We have concentrated where we generate electricity but decentralized its use, requiring a distribution system that today connects nearly every occupied building in Virginia to each other through electrical wires. Only our state road network is comparable to the electrical grid. Pipes for water and sewer stop at the edge of concentrated population centers, leaving rural residents to depend on separate wells and septic systems. Wires for cable TV don't extend into sparsely settled areas. Wires for telephone systems provided universal service in the past, but as more customers switch from landlines to cellphones that telecommunications network will shrink - perhaps, curiously enough, by starting to disappear first in urbanized areas where the cell towers provide reliable phone service.
Without the electricity transmission system, most factories would have to be located near power plants. Imagine a world where power could not be transmitted by wire... would houses also be located near power plants? Perhaps modern urban development would be concentrated around waterfalls and in southwestern Virginia near the coal fields - or we would have installed solar power units on every rooftop, and diesel generators in every garage. (The Amish in Giles County are a model - they choose to generate their electricity at their homes and stores, rather than connect to the grid.2)
Or imagine a world where a higher percentage of electricity is generated by wind energy, methane from landfills, co-generation at factories, etc. rather than at existing coal-fired and nuclear power plants. Renewable energy sources are widely distributed rather than centralized; for example, windmills may be miles offshore, as well as on mountaintops in rural western Virginia. To transmit electricity from those new sources to customers, the National Rural Electric Cooperative Association claims that a "large-scale expansion of renewables—enough to offset a big chunk of traditional baseload generation—begins with adding at least 30,000 miles of high-voltage transmission lines to wheel energy generated at remote wind farms and other facilities to urban load centers."3
There are complex electrical engineering factors that affect the management of the grid of power lines that connect suppliers with customers. In bulk power transmission, the voltage and the phase transmitted from the "sources" to the "sinks" must be balanced. In the "good ol' days" for the last 80 years, utilities have been regulated so generation, transmission, distribution, and billing for electricity use was consolidated in one company for a specific geographic area. In return for a monopoly control on providing electricity and a commtment to service all customers, the State Corporation Commission regulated electricity rates so Virginia utilities earned a steady profit.
With deregulation, the number of suppliers, marketers, and purchasers of power is far greater, and the accounting for power transmissions is far more complex. When a power plant goes off-line or a solar flare disrupts transmissions, the grid's ability to move power from source to sink at the correct voltage is affected. In July, 1999, the PJM Interconnection (P=Pennsylvania - J=New Jersey - M=Maryland) had to reduce voltage 5% before it reached peak load on July 6, 1999.
Electricity delivery is not as straightforward as the delivery of mail by the Postal Service or packages by FedExpress, and training is not simple. The transmission lines (the wires on the tall towers you see crossing the countryside) transport electricity. As population grows and people use more electrical appliances in the home, demand for electricity is rising. New "electricity highways" are constructed by adding new wires to existing towers, or occasionally constructing a new set of towers. Such construction can be politically difficult; few people consider transmission lines to be esthetic, and some question the safety of living near them.
Virginia Power purchased the rights-of-way of the failing Washington and Old Dominion Railroad in the early 1960's, to acquire a corridor for a new transmission line to supply the growing Northern Virginia region. Only after some contentious discussions was the route also made into a bike trail for recreational use.
The controversial AEP proposal to build a 765 kilovolt power line from its coal-fired power plant in Wyoming, West Virginia to Cloverdale, Virginia illustrates how an understanding of physical and cultural geography can help shape a public policy debate:
Electricity is bought and sold for firm delivery under long-term contracts and on a "spot" market to meet short-term demand. When Virginia Power acquires electricity from the New York Power Pool, the capacity to transmit the energy through Pennsylvania and Maryland transmission lines must be reserved along with the power itself. Since PJM Interconnection is a multi-state operation, the procedures and prices are affected by a Federal Energy Regulatory Commission (FERC) tariffs. Arrangements for delivery are handled in part through an online system, OASIS.
Virginia is included in two regions of the North American Electricity Reliability Council - Southeastern Electric Reliability Council (SERC) and the East Central Area Reliability Council (ECAR).
Note than production of electricity is highly centralized. The economies of scale lead to large hydroelectric dams and coal-fired power plants and nuclear reactors, rather than numerous small ones. The Public Utility Regulatory Policies Act of 1978 ("PURPA") encouraged a shift to decentralized production of electricity (and steam). This was a side effect - primary emphasis of the legislation was to stimulate production from non-traditional, renewable sources. The ongoing deregulation of electricity is likely increase the number of electricity producers, spurring co-generation at many manufacturing facilities. From a geographical perspective, the current map of sites in Virginia creating electricity for sale is likely to have many more dots by 2010...
Traditionally you may consider it wiser to put a few eggs in many different baskets rather all eggs in one basket. According to that approach, creation of more power plants in Virginia should increase our energy security. Initially, every Virginia manufacturing facility created its own independent power from wood or water. If a water wheel or dam broke for one grist mill, others could continue operating.
Urban centers started to create electricity in a similar fashion. When Richmond established the first hydroelectric plant to power street cars, or when Manassas created its own hydroelectric plant on Bull Run, the cities built stand-alone systems unconnected to any other sources of power. If ice clogged the intakes in January, Manassas customers froze in the dark for a few days - or relied upon their wood stoves and kerosene lamps. When these and other plants were connected by a grid of transmission lines, however, it became less likely that failure/sabotage at one large facility could blackout a significant region of Virginia.
Still, the major utilities rely upon just a few major generating sources to supply nearly 7 million Virginian customers. A handful of nuclear and coal plants supply a steady base load of power 24 hours/day, while more-flexible natural gas and hydro plants can generate peaks of power for the surges in demand on weekday mornings and early evenings. The small PURPA-stimulated facilities, such as the waste-to-energy plant (incinerator) at the Lorton landfill in Fairfax County, are less-stable suppliers of power compared to the large centralized plants such as the Clover coal-fired plant in Halifax County.
The energy security provided through PURPA comes more from reducing the demand for imported oil than from adding more eggs to the basket. If you added up all the small generators, you'd be hard-pressed to replace Surry 1 and 2... and even with the flexibility of the power grid, all Virginians have experienced many temporary power failures.
Were it not for a sophisticated transmission system able to transfer power from suppliers are far away as Ontario and to adapt to drops/surges as plants change their production, we would not be able to assume the lights will come on when we throw the switch. The design of the Internet provides an interesting comparison.
The initial ARPANET design was intended to provide "survivability" for Department of Defense communications, even if major communications centers were obliterated by a nuclear attack. Instead on relying upon a few centralized switching centers, the Internet was designed to rely upon alternative routes in an interconnected grid of telecommunications networks. Of course, the costs of building transmission lines for electricity are far greater than the costs for transmission on Internet Protocol packets - and unsightly too. Don't look for new power lines to be constructed as fast as you see microwave towers being erected or fiber optic lines being buried underground, especially in Northern Virginia.
One other comparison illutrates the geography of electricity in Virginia - the highway network throughout the state. It was designed intially to get crops from farms to market, and is now used to get manufactured goods to market (i.e., trucks on I-81 and the Woodrow Wilson Bridge) and employees from home to work. In hilly areas such as Buchanan County, a blockage of one road will dramatically interfere with local transportation. In other areas, such as Shenandoah County, there are many alternative roads that will allow drivers to reach their destination without waiting for the blockage to be cleared.
Public investment in mass transit increases dependence upon centralized systems, reducing flexibility to adapt to changing situations. Highway bridges and tunnels in particular are weak points, comparable to the interties connecting different electrical grids. Radio stations provide highway traffic reports "on the eights" or "every ten minutes," indicate the dependence on just a few routes for navigating the urban centers in Virginia. In places such as Arlington County and Hampton, local roads provide multiple choices for local traffic... but the limited backbone of Interstate and arterial highways is highly vulnerable to disruption. One accident and poof: 15,000 people will be late to work. There are now Internet traffic reports. Think the day will come when you are accustomed to hearing an electricity transmission report on the radio?
Bottom line: the story to watch re: Virginia electricity is not the easy-to-grasp changes in the locations of the generating plants, but instead the hard-to-see changes in the electrical distribution system. Deregulation of production, together with the inflexibility of the grid, will lead to public policy debates on ensuring fair access to the grid.
The Internet may be the media darling-du-jour, but you can be the first on your block to understand that electricity generation is the story-in-the-wings. Henrico County and other communities debated imposing open access requirements to Internet Service Providers (ISP's) before renewing licenses for cable TV networks in 1999. The politicians considered mandating that the cable networks permit customers (i. e., voters...) to choose ISP's not associated with the cable company.
Until AOL bought the Time Warner cable network, that Virginia company led the charge for open access. Onced Time Warner owned a critical mass of both generation facilities for Internet content and distribution channels via cable, the company changed its emphasis. Watch for comparable shifts in emphasis as ownership of utilities change in the near future...