Page 64 - North American Clean Energy May/June 2020 Issue

energy efficiency
Elements of Surprise
IN AN INDUSTRY WHERE MOST CRITICAL INFRASTRUCTURE
is left outdoors to face the elements day in and day out, mother nature’s wrath is one of the many operational challenges that renewable companies must contend with. Whether you operate a solar farm or wind park, wind, lightning, ice and hail can all wreak havoc on valuable assets and equipment. And while damage to a single turbine or solar array is costly, the prospect of losing potentially all of your generating capacity due to a failed collection or gen-tie transmission line could be even more catastrophic. While great steps have been taken to mitigate those risks to the generating assets themselves, more work can be done to harden the balance of plant infrastructure, specifically overhead collection and transmission interconnects.
Over the last two decades, a significant investment in renewable energy has been made across the country. A disproportionate amount of that development has occurred in the American heartland. Turbines have sprung up like wildflowers from the gulf coast of Texas to Minnesota and North Dakota. Unfortunately, this part of the country also experiences the most extreme weather imaginable. Severe thunderstorms and even tornados can be a weekly occurrence this time of year for operations in this part of the
USA, which brings with it an increased level of damage risk. For those of you
that don’t live in Tornado alley, here is something to consider: all 50 states in the union have recorded tornado touch downs since 1950, even Alaska and Hawaii. No one is completely immune from this risk. So, while the threat may be more severe for some, every renewable operation should have a strategy in place to plan for and deal with failures and outages from extreme weather and anything else that mother nature can throw at you.
A recent tornado outbreak in Oklahoma inflicted catastrophic damage on a wind park’s gen-tie transmission line, leaving the entire site offline for an extended period of time while repairs were made. With all 150MW of generating capacity unavailable, the asset owner lost a
large amount of revenue, in addition to the restoration costs needed to bring the site back online. In total, five steel
by Grant Leaverton
transmission poles collapsed where a tornado tore through the line. The owner quickly mobilized an inspection team to survey the line for damage using a drone to capture high definition imagery. The data collected served two purposes.
First, it identified the failed towers, and provided identification of potential safety hazards for the restorations crews before they arrived. The enhanced situational awareness gave the line crews additional insight to help them accomplish their repairs safely and efficiently. Second, the inspection documented other portions
of the line where damage was less obvious but equally important. In one instance, critical hardware that supported conductor suspension assemblies had broken but not yet dropped conductor to the ground. A walking inspection would almost certainly have missed this hidden damage, leaving the line at high risk for another subsequent failure. The detailed drone inspection documented several storm related weaknesses that lines crews were able to fix along with the failed towers. To emphasize the risks further, this outage was the third storm related failure this site experienced on their transmission line in three consecutive years. Severe weather will likely continue to be a threat for these operations as long as they exist, so the value in routinely inspecting, strengthening, and hardening our balance of plant infrastructure cannot be understated. Here are some practical steps that every site owner should consider taking to make their renewable assets more storm ready.
64
MAY•JUNE 2020 ///
www.nacleanenergy.com