Since Juneau is not connected to a larger power grid, all the electricity consumed in our community must be generated locally. Over 98% of our power comes from renewable hydro generation, most of which comes from the Snettisham Hydroelectric Project. The rest of our hydropower is generated at our Lake Dorothy, Annex Creek, Salmon Creek, and Gold Creek Hydroelectric Projects.
But generating the power is only part of the process. The electricity then has to be delivered over transmission lines to power substations around town, and then distributed to the homes and businesses in the community.
A variety of problems can affect the power lines. Anything that allows the electricity to find a path to ground, or allows two wires to contact each other, such as a tree or animal in the line, causes a “short circuit” or fault. When this happens, large circuit breakers automatically open the line to prevent the flow of dangerous or destructive current. When these circuit breakers open, it interrupts the flow of electricity to everyone beyond the fault. If a fault happens on our main line from Snettisham, it results in an area-wide outage. If it happens on the line serving a single home, only that home will be affected.
Sometimes you may see the lights in your home dim or flicker momentarily. This can be caused by a fault and breaker opening in another part of the system, which briefly disturbs the electrical flow throughout the system.
Many of our lines go through very rugged terrain, or through heavily forested areas. AEL&P works hard to prevent outages from occurring. We routinely perform seasonal tree trimming, systematic equipment inspection and replacement, transformer/breaker testing, and infrared imaging to identify potential problems before they occur. In regards to tree trimming, we are authorized to trim trees within our right of way. Quite often, however, the trees that fall into our lines (as a result of heavy wind or snow) originate outside of the right of way, which makes them inaccessible during routine tree trimming.
Preventative measures aside, the lines in our community will always be susceptible to Mother Nature, wayward critters, and even people.
AEL&P serves more than 17,000 customers with electricity, 24/7, 365 days-a-year. The equipment that makes this happen works between 138,000 volts and 120 volts. Equipment wears out and -- when it does -- it lets us know with an outage. Some equipment may serve only a single home or business, while other equipment serves the entire city.
People are only human. Mistakes happen. The best examples of man-made outages include vehicles running or backing into our equipment, backhoes digging into cables, etc.
Weather is the big one. Heavy snow, ice storms and high winds take their toll. Tree limbs that contact our lines will always cause some sort of interruption. That's why we contract to keep them trimmed. However, there are a lot of trees between here and our Snettisham Hydro Facility.
Customers are encouraged to protect sensitive electrical equipment in their homes and businesses with surge suppressors, and may want to consider Uninterruptible Power Supplies (UPS) for important equipment.
If the power goes out at your house, check to see if your neighbors have power. If they do, then the outage is only affecting your home and we won’t know about it until you call us. If your neighbors are also without power, the outage is probably large enough that we know about it already. In that case there is no need to call unless you have information about the specific location or cause of the outage. During all outages, we keep the community informed through our website and social media pages. This works great if you or a family member has a smartphone handy. For larger outages, we report updates to our local radio stations. A battery-powered radio can keep you informed about an outage.
Our crews respond to all outages and continue working until power is restored to all of our customers. Even though outages will always be a fact-of-life with any electrical system, rest assured that we are committed -- 24/7 -- to keeping the lights on in Juneau.