Reliability of Alternative Energy Sources
Alternative energy, particularly renewable forms, can be a hugely beneficial resource. Alternative energy facilities require less maintenance than traditional generators, and the cost of operation is lowered even further by the fact that they are derived from resources that are readily available. This lower operating cost becomes even more significant when considering that the expense of the energy facilities dictates how much consumers pay to power their homes. An additional benefit is that alternative energy sources create practically no waste, making very little impact on the environment.
These benefits make using alternative energy seem like a no-brainer. However, methods of producing alternative energy can have their downsides.
How the Weather Affects Renewable Energy
Because so many renewable energy sources depend on the weather, they can be highly unreliable. If an area experiences a drought, the dam levels may fall and the hydro generators may not be able to run. Too many consecutive cloudy days can keep solar collectors from making power. Without wind, a turbine’s blades can’t turn and the device becomes ineffective. Essentially, when the weather condition that generates the energy is unavailable, so is the energy.
However, with the right location, weather-dependent sources can create a more reliable energy supply. Studies have shown that putting solar collectors in the Southwest (where it is rarely cloudy), and wind turbines in the Great Plains (where the wind supply is fairly constant), could allow America to run eighty to ninety percent of its electrical supply from renewable sources.
Making Wind Turbines Reliable
With a large enough power grid system, wind can be used as a more reliable energy source. For example, the Midwest Independent Transmission System Operator, or MISO, which is a wind-driven power grid for twelve Midwestern states, has a constant influx of power because when wind is not blowing in one area of the twelve states, it is blowing in a different area.
A modern development that is allowing wind turbines to serve as a reliable energy source is better forecasting. More accurate predictions of wind patterns, precipitation, cloud cover, and severities make it easier to forecast wind turbine outputs. This allows for an arrangement of turbines that optimizes energy output and makes wind far more reliable than it has been in the past.
More Reliable Forms of Renewable Energy
Hydro generators can produce a more consistent energy stream if built on a bigger scale. Larger dams can hold more water, which means—barring a very serious drought—there will be enough to continue moving through the dam’s generator even if the water supply goes down.
Another possible option for long-term reliability is geothermal systems. This form of power captures steam from brine fields underground and uses the heat to turn a turbine, which creates electricity. These brine fields are constantly giving off steam to be used as a continuous electrical source, as opposed to it fluctuating with the weather.
However, while the heat that runs a geothermal plant is in no danger of running out, the devices that turn it into electricity do have a finite life span. These systems wear out after a few years and need to be replaced, making the creation of geothermal power more expensive—and more difficult to maintain—than other forms of alternative energy.
All alternative energy sources have their individual benefits and drawbacks. Investors have to balance capital investment, maintenance costs, staffing, fuel surety and market opportunities. Utilities must consider mandated purchases of renewable energy, the intermittence of certain generation, and the need to acquire additional ancillary services to ensure Bulk Electric System reliability. Therefore blended portfolios that include a mix of conventional and alternative energy development will result in the most cost effective and reliable strategy to serve the needs of North America in the future.
Kevin Conway is the Vice President of Operations at Intellibind, the leader in services to meet NERC Reliability Standards Compliance requirements