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IoT & M2M Iridium Utilities & Renewables

August 8, 2023

Revolutionizing offshore wind farm maintenance: the power of wireless connectivity

The offshore wind energy sector is rapidly expanding, with pioneering nations like the UK, Germany, and the Netherlands, followed by China leading the world with an impressive 23.9 GW offshore wind energy production capacity. Recognizing its potential, the United States, under President Biden’s leadership, has committed to constructing 30 GW of offshore wind projects by 2030, a move that could power more than 10 million homes with clean energy. Brazil also joins the ranks with an ambitious plan for 72.2 GW capacity, second only to the UK’s planned additional 78.5 GW.

Offshore wind power offers distinct advantages, including consistent high wind speeds unobstructed by terrain or buildings, resulting in reliable energy output. However, this comes with significant costs. The harsh marine environment exposes turbines to corrosion and oxidation, leading to higher risks of damage. Repairing offshore turbines is not only more complex but also more expensive and hazardous compared to onshore wind. Consequently, offshore wind production costs exceed those of solar or onshore wind, with floating turbines costing $133 per megawatt hour and fixed-bottom turbines at $78 per megawatt hour, compared to $34 per megawatt hour for onshore wind.

We firmly believe that satellite Internet of Things (IoT) technology holds the key to addressing these challenges and ushering in a new era of efficiency and safety. Satellite IoT has the potential to reduce production costs and enhance worker safety in offshore wind energy. In the following sections, we will explore the transformative role that satellite IoT can play in this vital industry.

Why offshore wind costs more

Nearly 38% of offshore wind farm expenses go towards maintenance. Let’s dig into the reasons behind this.

  • One key reason for higher costs is equipment failure. On average, each turbine has about 8.3 issues every year. These include 6.2 minor fixes, 1.1 major repairs, and 0.3 instances where major parts need replacing. All of these repairs add up, making the expenses go up.
  • Maintenance crews are a big part of the cost. Major replacements take around 116 days and need 9 technicians. Minor fixes take 7 days with 3 technicians. Bad weather often causes delays (“no access days”), making maintenance take longer and costing more.
  • As equipment gets older, costs go up even more. According to some analysts, the yearly operating costs start at $234,000 per MegaWatt in the beginning but can jump to $542,000 per MW/Year when the turbine is 15 years old.

Reducing costs: the solution lies in predictive maintenance

The most effective way to cut these expenses is through predictive maintenance. Supervisory Control and Data Acquisition (SCADA) systems allow operators to watch for problems or reduced performance and use advanced data analysis to foresee maintenance needs.

Predictive tools like Condition Monitoring Systems (CMS) play a crucial role. These systems gather and study around 250 physical data points, such as torque and force measurements, noise patterns, electrical strain, oil quality, and main bearing health. Sensors collect this information, and then AI or machine learning make the predictions more precise while reducing false alerts as the system becomes more established and the number of installations grows.

The advantages of using CMS are easy to understand. One provider of monitoring systems asserts that 90% of developing issues are detected 5 months before they become a problem, leading to a 175% annual return on investment due to less downtime and up to a 50% decrease in urgent maintenance trips.

Predictive maintenance drives 175% annual ROI for offshore wind farms

Moreover, enhancing quality control diminishes the chances of accidents, ultimately leading to potential reductions in insurance costs.

An integral component of this procedure involves sending sensor data to the cloud and subsequently to the client’s IT system, where the data is gathered, stored, and analyzed.

Typically, sensor data is transferred via underwater cables, providing numerous advantages: it’s swift, secure, and offers cost-effective transmission of substantial data volumes. Nevertheless, wired communication does come with certain drawbacks that can be mitigated through the implementation of a wireless alternative at the same location.

Why have both wired and wireless networks in an offshore wind farm?

For those who already have a wired connection to their wind farm, integrating a wireless system as a complement is a strategic consideration. Integrating new sensors into a wireless network is far less complex than adding points to an existing legacy system. To capture essential data, you simply position your sensors where needed and activate them. This eliminates the need for extensive cabling, resulting in both time and cost savings, and expediting access to additional sensor data.

Furthermore, by establishing a dedicated wireless network for your SCADA data, you ensure independent transmission of findings, unaffected by other data sources. This real-time information empowers maintenance teams to make prompt decisions on which issues to address and when. According to Turbit, this swift action can boost output by up to 5% through faster corrective measures.

While creating a new offshore wind farm with exclusive wireless connectivity can cost as little as 10% of the wired alternative and has quicker implementation, it’s important to note that satellite and cellular connections typically involve monthly usage fees and are suitable for relatively moderate data volumes. Hence, a blend of wired and wireless setups is often explored by operators in practice.

However, introducing a wireless network isn’t always straightforward for offshore wind farms, particularly when they exceed the reach of cellular networks. While 4G/LTE services generally extend up to 12 nautical miles from the coast, wind farms can be situated as far as 43 miles offshore, resulting in a coverage gap.

This gap can be bridged with a private cellular network, offering substantial throughput and robust data security. Nevertheless, the setup process for this option can be both expensive and time-consuming.

Exploring effective wireless connectivity: LoRaWAN and satellite synergy

A blend of LoRaWAN technology and satellite connectivity is gaining considerable traction for this purpose. LoRa networks are easy to establish and cover a wireless span of approximately 16km. Engineered specifically for IoT data, LoRa-enabled sensors boast prolonged battery life while handling smaller data volumes.

The process involves aggregating sensor data from each turbine in a LoRaWAN gateway and then employing a single satellite transceiver to dispatch the data to the cloud. Modern technology readily facilitates this integration. For instance, a device like the RockREMOTE Rugged, equipped with an omni-directional antenna, can be positioned on a turbine, maintaining a consistent connection via the Iridium satellite network. This connectivity remains unaffected even if the turbine shifts position.

This combined approach, blending a Wide Area Network with satellite connectivity, minimizes the necessity for individual hardware on most turbines to connect to the satellite network. Only a single ‘master’ turbine, along with the gateway, requires this specific hardware. The gateway additionally contributes to reducing data transmission costs by offering edge computing capabilities. This may entail reporting exceptional occurrences, where only data points falling outside predetermined parameters are transmitted.


Is satellite data transmission expensive?

The landscape of satellite data transmission has undergone a significant shift due to the emergence of new operators such as Starlink and the forthcoming Amazon Kuiper Project. This influx has led to a substantial reduction in the cost of utilizing satellite networks for data transmission. Long-standing network operators, with a track record of reliability, have diversified their offerings to remain competitive against these newcomers (read more about satellite connectivity costs).

Additionally, it’s worth noting that partnering with established network operators like Iridium and Inmarsat comes with an extra advantage. Their data transfer mechanisms hold the trust of governments and militaries across the globe. Given that wind farms qualify as critical national infrastructure and are projected to become more appealing targets for cyber-crime in the near future, having access to highly secure data transfer options carries significant importance.

Who else gains from wireless sensor data transmission?

Beyond the operations team that interprets and acts on the recommendations provided by the Condition Monitoring Systems (CMS), there’s another group that benefits from wireless sensor data and analysis: the maintenance crews. These essential individuals, often stationed on offshore support vessels (OSVs), play a pivotal role in ensuring the seamless execution of offshore projects.

The same data collected by sensors and sent via satellite to the cloud can also be transmitted to the OSVs. This direct data transfer empowers maintenance crews to efficiently prioritize tasks without waiting for instructions from onshore teams. Real-time measurements of wind, humidity, wave height, and weather patterns are crucial for the safety of these maintenance workers. This sensor data doesn’t need to be sent through the main fiber communication channel, as it is vital information chiefly for the maintenance teams.

Recommended satellite IoT hardware for OSVs

While offshore support vessels (OSVs) often employ robust VSAT systems for crew communication, we suggest adopting a separate, lighter-weight system for transmitting IoT and tracking data. This approach serves as a fail-safe measure and optimizes bandwidth utilization.

The Thales VesseLINK emerges as an excellent solution for this purpose. It leverages the Iridium satellite network, which boasts 100% global coverage, and employs omni-directional antennas. This eliminates the need for realigning the device as the OSV changes position. The network’s Low Earth Orbit (LEO) configuration ensures low latency, clocking in at under one second. Moreover, the use of the L-band frequency for data transmission, impervious to weather conditions, makes Iridium-enabled devices well-suited for mission-critical data.

The Thales VesseLINK comes in two versions: VesseLINK 200 and VesseLINK 700. The distinction lies in data speeds. The former is optimized for IoT data and basic voice/internet access, delivering data speeds of 176 Kbps. The latter offers high-speed internet with speeds of 700 Kbps and establishes a WiFi hotspot covering a range of 300 meters. While it’s capable of far more than just transmitting IoT data, it excels in doing so under any circumstances.


Another satellite transceiver worth considering is the RockSTAR. This portable device can link up with wearable sensors such as heart rate and body temperature monitors. It also offers two-way messaging and an SOS feature. Utilizing the Iridium satellite network, this data can be sent to safety teams, enabling prompt interventions when necessary.

Primary, secondary, or backup communication

A crucial aspect to consider in satellite connectivity for your offshore wind farm is its value as a backup communication method in case your main connection to the turbines encounters issues. Underwater cables are susceptible to damage from trawlers, environmental factors, or even deliberate sabotage. With satellite serving as a contingency, you retain the ability to both halt or initiate turbine operations and communicate with your personnel. This instant infrastructure remains impervious to weather conditions, remains independent of terrestrial networks, and maintains a high level of security.

Talk to the experts

Having collaborated with both renewable energy firms and instrumentation manufacturers for decades, we've witnessed the transformative evolution of satellite IoT over the years. This evolution is now unfolding at an unprecedented pace.

We stand ready to assist you in navigating this dynamic landscape, aiding you in making informed decisions that will yield lasting benefits well into the next decade. Reach out to us, and we'll offer you unbiased, expert guidance to propel your endeavors forward.