Since ancient times, wind has been a reliable energy source. Though it is not a new source of energy, the demand for wind power has risen over the last few decades. As an abundant and inexhaustible resource, wind provides a form of sustainable, clean energy. Additionally, generating wind power can lead to community benefits like greater job creation.

Both offshore and onshore wind farms provide different advantages and play necessary roles in the continued use of wind as energy.

What Is Onshore Wind?

An onshore wind farm is a wind farm located on land. These wind turbines use the natural movement of the surrounding air to generate power. Typically, you will find onshore wind farms in more remote, rural areas of the country, where the necessary acreage is available and buildings and other structures cannot disrupt the wind flow. The construction of wind turbines on land involves considering common wind patterns and speeds for optimal efficiency.

For the necessary energy transfer, onshore wind turbines must rotate at a consistent speed. As the blades rotate, their energy first moves to a generator and then to voltage cables. Finally, the energy moves to a substation, converting it to usable electricity before distribution.

Advantages of Onshore Wind

Onshore wind farms offer many notable advantages, including:

1. Cost Effectiveness

Compared to offshore wind turbines, onshore wind turbines are more affordable due to lower infrastructure and maintenance costs. Since they are placed on land, it is easier to access them to make repairs, if necessary. Accessing blades, motors, and other necessary parts is less expensive.

2. Positive Effects on Local Economies

Wind power benefits local economies. The construction of wind turbines in groups or farms creates jobs and energy savings that benefit communities.

3. Simple Energy Transfer

A notable advantage of onshore wind is how easy it is to transfer the generated energy to the local grid. An onshore wind farm can rely on existing infrastructure to feed power into the local power system, that allows the community to access and benefit from the power. There is often no need to take extra, costly steps to configure the energy transfer.

What Is Offshore Wind?

Unlike onshore wind farms, offshore wind farms are built on bodies of water, ranging from oceans to large lakes and fjords, where they harness the surrounding wind. In relatively shallow water, offshore wind turbines can be directly attached to the sea floor. In deeper water, turbines will need to be based upon floating foundations, which are then held in place by complex anchor systems.

Advantages of Offshore Wind

In the coming years, offshore wind is expected to grow, as the installation of wind turbines over water has key advantages. Two of the top benefits include:

1. Efficient Energy Generation

These farms can be more effective at creating energy than onshore wind farms, as sea winds are more robust and blow in the same direction. As a result, an offshore wind farm could create more electricity than an onshore wind farm of the same size — winds on land are less predictable and typically less strong. Additionally, offshore wind turbines can be much larger, which contributes further to their efficiency.

2. Minimal Intrusion

Issues like noise pollution and visual disruptions are less significant with offshore wind farms. Projects are strictly regulated in order to minimize the potential environmental impacts of offshore farms on navigation, commercial fishing, and marine life. In some cases, offshore wind farms can actually enhance marine life by acting as artificial reefs.

Variables to Consider With Onshore and Offshore Wind

While both onshore and offshore wind energy initiatives have many advantages, they come with potential challenges. As wind power becomes even more advanced, developers innovate to counter potential issues.

Challenges and Mitigation Measures for Onshore Wind

Here are some mitigation efforts to consider to ensure the public and local economy benefit as much as they can from onshore wind power:

Visual impact: Environmental impact assessments often consider the visual impact of wind turbines due to their size. Developers normally space them out, increase the distance between viewers and the wind farm, and revegetate road cuttings to help reduce their visual impact. Other innovative ways to reduce the visual disruption of the landscape include painting the turbines with off-white or gray non-reflective paint to help them blend in the environment.
Auditory impact: Blades can operate with less auditory impact through the use of noise-optimized blade designs and the adjustment of their speed. Strategically placed acoustic barriers and insulation around turbines can absorb and reduce noise levels.
Intermittency: Onshore wind energy is variable and dependent on weather conditions. This can lead to fluctuations in power output. By combining wind energy with other renewable energy solutions and smart grid technologies, fluctuations in power output and disruptions can be lowered.
Land use: Wind farms are spacious. When choosing a site, developers consider the landscape and land availability to minimize the impact on ecosystems and agricultural activities. For example, sharing land with grazing livestock can lower the loss of land.

Challenges and Mitigation Measures for Offshore Wind

Offshore wind farms provide benefits like generating more energy while being less intrusive. However, here are some of the challenges, along with mitigation measures commonly employed:

Construction costs: Offshore wind farms have more complex logistics when it comes to the installation of the towers and their larger structures. The installation process must account for construction, foundation size, installation, and grid connection. The use of innovative technology to create leaner designs that use less raw material can reduce the construction costs of offshore wind farms. Floating wind turbine systems can also be a cost-effective solution. Additionally, innovative wind-catching systems increase the number of turbine blades on a structure while lowering the number of floating devices in the water.
Maintenance and repairs: Due to the environmental factors related to different bodies of water, offshore wind farms have more unique maintenance requirements than onshore wind farms. To minimize the impact of seawater and corrosion, it is important to enhance the structural integrity of offshore wind farms. Through real-time monitoring, predictive analytics, and robotic inspection, designers can significantly enhance the longevity and efficiency of wind farms.

Safety Training to Equip You for the Wind Industry

Meeting increased energy demand has become a global challenge. Fortunately, wind power is an effective solution, and both onshore and offshore wind farms provide avenues for creating renewable energy to meet that demand.

Those interested in working in sustainable energy, particularly in the offshore wind industry, require extensive training. At the Maritime Institute of Technology and Graduate Studies (MITAGS), the Global Wind Organization – Basic Safety Training course, will provide the mandatory entry-level credential required by all employers.

For more information about the course or any of our training programs, consult with a MITAGS Academic Advisor today.

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