Flying high: innovations in wind energy and load cells

Published On: August 13 2021

Back in 2018, we dealt with a Scottish company who were at the cutting edge of Airborne Wind Energy (AWE) production. Three years on, we thought we’d wing past their website and see how they were getting on.

Now part of Norwegian company Kitemill, we were amazed to see how many companies and universities across the world are working on this highly materials-efficient method of energy production.

Let’s go fly a kite

We’re not sure how long it is since you flew a kite, but we’re sure you remember the frustration as you fought a kite turning circles in high winds. Yet it’s this very action that helps this most modern of kites harness wind energy at high altitudes.

Unlike wind turbines which operate at fixed heights up to 100metres above the terrain, AWE kites can soar to reach much higher altitudes. The higher they can go, the stronger the winds. For example, at an altitude of 1000m, the average wind speeds are 11m/s compared with 5m/s at 100m. That means the available power is 580 W/m2 as opposed to 80 w/m2.

A kite that looks like a plane

Looking like a large model aircraft, the kites generate power by pulling a cable from a winch as it climbs into the sky. Lifting off using battery-powered batteries, the kite quickly soars to its operating height.

Once in position, as KiteMill explain:

“The kite flies in a spiral and creates a tractive pull force to the line. The winch generates electricity as it is being reeled out.”

At the end of the generating phase:

“The tether is retracted back on the winch drum as the kite flies directly back to the starting point. The entire return phase consumes less than 2% of the power generated, and requires less than 20%of the total cycle time.”

Wind energy cabling and load cells

Like many wind energy installations, load cells are involved in tension monitoring the forces on cables. With the kite, we presume load cells ensure the tension is within safe limits and probably play a part in reeling in the kite should the winds exceed safe limits too. (In the case of wind turbines, it’s the cables that tether a wind turbine tower to its foundations or the sea bed that are monitored using load cells.)

Recycling wind turbine locations

As wind turbines reach the en of their life, they need to be removed and replaced. That often means that their expensive platform base remains unused during the changeover (if reused at all). The kite system can be installed on this most reboots of bases, providing a temporarily solution to keep producing power, and utilising the existing infrastructure too. It can also be deployed in remote areas with no existing power infrastructure. Very neat!

High altitude balloons

Another example of harassing winds at high altitudes is the H.A.W.E. (High Altitude Wind Energy) by Omnidea. In this case, the project:

“Produces energy from the aerodynamic forces acting upon an airborne airfoil-like craft. If connected to the ground through a tether cable, this apparatus can convert wind energy into electrical energy.”

In this case:

“S-type load cells (and) S-type assembly such as hook and eye bolts in combination with a transmitter … convert the mV/V signal into a 4-20mA signal to measure the pulling force of the HAWE Balloons.”

Load cells and wind turbines

For more on load cells and wind power, see our articles:

Load cells for your renewable energy project

If you need load cell for any renewable energy project, call us. We can design and manufacture load cells to your specific requirements, or choose from our extensive stock as our online land cell shop.