Regional climate change is altering the environment around us, driving increasingly extreme weather events that are creating unique operating challenges for renewable energy infrastructure. Unfortunately, this increase in weather frequency and intensity is occurring during a period of booming growth in wind and solar energy generation, with more projects coming online amidst a global push for decarbonization.
The combination of rapid adoption and increasingly damaging weather events is testing equipment designs, safe operating ranges and control instrumentation limits, creating concern among those who own and operate renewable generation assets. It can be difficult — but not impossible — to protect these valuable investments from risk.
To get there, owners and operators must understand the climate risks associated with their regional location; determine and integrate the proper design criteria and operating philosophy; select the correct and components and embrace remote monitoring to not only prevent damage but to get their systems back up and running as quickly as possible.
Changing Climate = Changing Risks
In wetland areas, our changing climate is causing flood plains, shorelines and wetland boundaries to shift and reposition, which can undercut wind and solar structures and increase the risk of flooding in the next extreme weather event. Valuable assets can be severely damaged by rising water levels and floods, prohibiting access to sites to perform maintenance and repair.
Ambient temperatures are also changing, impacting equipment operation and performance. Instrumentation and sensors can overheat when temperatures exceed norms, requiring curtailment and additional cooling measures. The opposite is true as well – as evidenced in Texas in early 2021, freezing temperatures can create serious operational risk. Unfortunately, both situations take systems offline when they are most needed to support load.
Increasingly high winds, changing wind speed and wind load can also damage structures, causing them to fail and damage equipment, causing outages and costly replacements. Climate change is also driving increasingly extreme wildfire danger: a combination of high winds, rising temperatures and aging infrastructure has caused the nation’s largest utility, California’s Pacific Gas & Electric, to experience massive property destruction, long-term outages and devastating fatalities every year since 2017.
Design Criteria, Operating Philosophy are Key
No matter where projects are located, when it comes to developing renewable generation facilities for wind and solar, owners and operators must approach the process from a sighting and planning standpoint to help ensure resilience and reliability. The proper design criteria and operational philosophy must consider and account for any extreme weather events that can occur.
Black & Veatch recently served on a failure-mode analysis team on a fixed-tilt PVA (Positive Vorticity Advection) project in Virginia that failed due to snow load. The team found that several factors – starting with the criteria that were used to estimate the snow loads and how that translated into the selection of racking material, steel thickness and corrosion resistance – contributed to a major failure in the array.
That said, having a consistent design basis for constructing new assets is only as good as the information it is based upon, and it can be difficult to obtain reliable data that would inform the type of extreme weather event that might occur.
For example, the U.S. Government Accountability Office recently examined the Federal Emergency Management Agency’s (FEMA) flood hazard maps and other flood risk products only to determine that the materials “didn't reflect the best available climate science or include information on current flood hazards … FEMA’s flood mapping program may take years to address these issues and has been operating under an out-of-date plan.”
Hurricane-level winds are also becoming more frequent, and wind speed and wind load are now presenting higher than code, making it all a bit of a moving target.
Having a standard approach for reviewing asset risk would also help prioritize upgrade projects. This may require consulting climate experts on the appropriate design basis and margins to future-proof assets, and include studies and mapping based on climate change modeling. No matter the project, owners and operators would be well-served to perform siting/routing due diligence studies to review environmental permitting implications before advancing to the execution plan and EPC bidding.
Selecting the Right Parts
A lot goes into selecting the right components, and there are subtle differences in product selection and racking selection. This is where the proper design criteria and operational goals are critical: components located in wet, humid environments will encounter different challenges than those in dry, high-altitude climates.
Granted, solar panels and wind blades have inherent degradation built into their life cycle and owners and operators should be cognizant if there was a higher failure mode than originally anticipated – and was this a design consideration or something else?
Owners and operators should also consider historical performance and the strength of the original equipment manufacturer while also looking at the operating history area assets. Though rare, this is where operators can lean on one another for recommendations and advice, and share lessons learned.
As for projects that have already begun or are being repowered, this presents an opportunity to reassess the additional criteria. For more established projects that are not hitting their operational benchmarks or key performance indicators, this could be an opportunity to reassess and improve operations.
Remote Monitoring & Data Analytics
The use of remote monitoring paired with data analytics can help mitigate weather-related issues, helping to ensure continued operation. Early anomaly detection can detect issues before they become critical. On a recent project, the Black & Veatch team detected a small change in lubricant oil temperature on a critical fan following a cold snap, which led to the discovery of a broken hinge on a skid enclosure that ended up freezing a water line. Asset monitoring detected the issue early enough for the operator to thaw the frozen line and prevent downtime.
Predictive data analytics based on historical data can model expected behavior and extrapolate it for future events. For example, there are several reasons behind a high lube-oil temperature; it could be the ambient temperature, or the heat exchanger needs to be cleaned or replaced. Modeled behavior can not only give an indication of how things should be running but can help determine the root cause.
Routine asset assessments and inspections can help mitigate the risk of failure and unplanned outages. Owners and operators should develop proactive inspection programs and prioritized maintenance plans and identify when upgrades could best mitigate risks. Drones equipped with high-resolution photography or live feeds are becoming an increasingly popular tool to monitor asset wear and tear. A combination of drone and in-person inspections and desktop data review can help owners and operators determine, prioritize and reduce risk.
Getting Back Online
Once a system has gone down, owners and operators must triage and figure out how to get their systems up and running in a timely manner. Having available inventory plays a key part in this; if there are blade failures, gearbox failures or any other equipment issues, how fast can the owner/operator navigate supply chain dynamics to procure the necessary replacements? And it’s not just the equipment, but also the labor required to get everything plugged back in.
The future of extreme weather may be hard to predict, but with the proper tools and preparation, critical infrastructure providers can be ready.
