By Gian Schelling, renewables business development manager, Hitachi ABB Power Grids
Developers across the country are building large-scale solar projects at an incredible pace, helping the industry do its part to move the world toward a more sustainable future. But the auction-driven push to lower the levelized cost of energy (LCOE) combined with changing weather patterns are forcing energy companies to rethink how they optimize overall yield, further decrease LCOE and keep PV plants online in harsher environmental conditions.
Unfortunately, large solar plants are becoming increasingly vulnerable to extreme weather from climate change: storms, temperatures and precipitation continue to grow unpredictably. This puts arrays at risk of decreased output or being knocked offline completely, creating penalty payments for unplanned outages or reduced production as well as costly maintenance and repairs. Communications systems give operators visibility into onsite weather conditions and enable remote-automated or manual equipment control.
Massive data from deployed sensors like anemometers, irradiation sensors and the arrays themselves allows operators to predict extreme conditions and take action to keep systems up and running remotely from a central operations center.
Still, building large communication networks capable of handling the explosion of monitoring and performance data is a complex and expensive undertaking. This is particularly true for brownfield applications, since these plants typically already have power cables (including fiber optic communication infrastructure) laid and connected to existing equipment during the installation phase. It would be costly to upgrade and scale for additional sensors such as weather measurement devices.
Wireless communication networks for existing projects
Wireless communication networks can provide cost-effective, scalable and reliable connectivity for solar projects. In fact, deployed wireless project examples showed up to 75% cost reduction when expanding existing wired communication networks in installed PV plants with wireless vs. more wired communication infrastructure. But we cannot just put a wireless device on an inverter and call it a day. Power companies need to rethink how they design, plan, build, update and scale communication networks in a cost efficient, manageable way.
Here are three things to consider when building out solar wireless communications networks:
1. Consider a private network
Public utilities are seeing an increase in cyberattacks that seek to disrupt economies or hold systems and data ransom in exchange for a large payout — the larger a power generation asset is, the more important its yield’s impact has on an overall region, hence the more attractive it is for cyberattacks. For monitoring of mission-critical machine-to-machine applications, it is important to consider a private and dedicated wireless communications solution that allows for more stringent control and security of the network. These private solutions can be deployed anywhere around the world for dedicated, multi-application use and are therefore more reliable and secure with end-to-end protection built in. In fact, new regulations from governments and pressure from lenders insist on following security standards such as NERC CIP in the U.S — protocols that may be prohibitive of public infrastructure.
2. Insist on plug-and-play scalability
When a developer expands an existing solar project, it’s critical for them to be able to scale wireless communications networks along with it. Every time a new array, inverter, prognostic, weather instrument or other sensor is added, it needs to be connected, configured, tested and integrated into the grid. Operators would benefit from a solution that automates much of the provisioning process, enabling them to plug-and-play new devices without significant human interaction.
3. Implement self-healing technology
A self-forming, self-optimizing and self-healing meshed architecture renders wireless communications less prone to outages. Imagine that a large storm takes out the connection to an anemometer. Typically, in the case of wired communication infrastructure, a technician would have to go out into the field and either repair or replace the equipment. Conversely, a mesh would automatically reconfigure the network to close the service gap. Operators could then work in the background from the remote control center to get the sensor back up and running without causing a disruption of service. Eliminating the need to send a technician into the field while avoiding outages reduces operational costs and extends the lifetime of the asset.
Wireless is the future
Extreme weather and other environmental concerns are putting large-scale solar projects at risk. Power companies must protect their solar assets through remote asset monitoring, but the explosion in data is overwhelming existing communication networks and forcing companies to rethink wired infrastructure for specific applications. Wireless communication networks have the ability to scale connectivity, extend the lifetime of assets and save power companies significant OPEX costs over the lifetime of the solar project. It’s just a matter of choosing the right wireless solution for your solar plant needs.
