Ground stations for Airborne Wind Energy
Airborne wind energy
Airborne wind is a great complementary to conventional wind turbines
An AWE system weighs only 10-20% of a conventional wind turbine.
Even small units can reach strong winds at high altitudes, it just takes a long tether. And when wind speed increases just 25%, there is double the amount of energy to harvest.
AWE is easy to transport and install. All installations are at ground level, and foundation is at a minimum.
Easy transport and high reach allows for deployment in forests and hilly areas where conventional wind turbines are not practical, i.e. the global wind power potential is dramatically increased.
At 1MW, a stiff drone of approximately 30m wingspan is sufficient, and the ground station can be built into two 20ft containers. Alternatively, a soft and foldable parasuite-like drone is used with a similar ground station. Such compact solutions make AWE attractive, even for temporary installations.
For much more insight, we recommend visiting the homepage of Airborne Wind Europe
Ground stations with power smoothing
In close cooperation with our partner Imenco AS, our vision is to industrialize ground stations. Our ground stations are designed to contribute to low cost of energy. We have identified significant scaling- and volume advantages with our technologies, securing an excellent economy of scale.
Digital hydraulic pump-motors control the winch. They have very high efficiency, also at part load, negligible inertia, precise torque control and significantly lower cost than electrical generators+VFDs+gearboxes.
Energy storage in compressed nitrogen increase the value of the electrical power and decouples the winch operation from the electrical outlet.
This smoothing technology is proven during half a century in the oil and gas industry, where reliability is of utmost importance. It has negligible degradation, almost infinite lifetime and a superior cycle efficiency.
For special purposes like take-off and landing, very high power levels can be released or absorbed.
Electricity production starts with a high-efficient hydraulic motor driving an electrical generator.
The choice of generator type is flexible, yet preferred is a synchronous machine, which offers a robust, energy-efficient and cost-effective solution. Absence of power electronics enables output voltages up to 15 kV. High voltage is especially valuable at utility scale, where it significantly reduces the need for step-up transformation (a challenge that is often forgotten in the evaluation of ground station technology).
Significant LCoE reduction
Energy storage with no degradation and "infinite" lifetime
Proven off-shore components
Condition monitoring for preventive maintenance
Cost-effective scaling and short time to market
We combine our concepts and components for power capacities up to +1.5MW rated power.
The advanced hydraulic technology scales nicely for to multimegawatt size, yet component development may be needed.
The choices of technology dictate the material options. Not only weight has an impact; re-use, recycling and how sparse materials are from nature may be even more important. A ground station based on hydraulics has very little sparse materials and a high degree of easy-to-acces materials, mostly iron (Fe).
Energy storage in pressurized N2
No power electronics*
No permanent magnets**
Accumulator cylinders and N2 bottles have ”infinite” life with minimum maintenance
Digital winch drive motors and generator drive motors can be refurbished with new wear parts
All parts except for control electronics, solenoid valves, UPS and generators are made of cast iron and steel, i.e. there is low risk of material shortage due to political or environmental restrictions and both re-use of components and recycling of materials are easy
* Compared to electrical ground stations. Small amounts of power electronics is used to control the synchronous generator and operate valves and auxiliary systems
** Compared to electrical ground stations. Small amounts of permanent magnets are used in sensors and auxiliary system