StratoSolar
+1 408 821 7036
  • Home
  • Technology
    • Key Enabling Insights
    • PV Generation Platforms
    • Gravity Energy Storage
    • Communications Platform
    • Proven Technologies
    • Example Complete Energy Solution for the UK
    • Common Concerns >
      • Airspace
      • Hurricanes
      • FAQ
    • Gallery of Images >
      • Platform Shadow Videos
      • Japan Energy Solution Map
      • 2050 World Energy Sankey Diagram
      • 2050 Synthetic Fuel solution
      • 2050 Electricity solution
      • Climate Change Videos
  • Benefits
    • Low Cost Generation
    • Low Cost Energy Storage
    • Cost Reduction Roadmap
    • Sustainable and Scale-able
    • Zero Carbon
    • Energy Security
  • Contact Us
  • Blog
  • Login
    • Presentations
    • Gallery >
      • PV Documents >
        • PV Big Picture policy level document
        • PV California deployment
        • PV Japan deployment
        • PV UK deployment
        • Wind and Buoyancy Forces
  • Related Sites
  • Solve for x Videos

Station keeping, high altitude, Drone and Airship weaknesses

10/15/2014

Comments

 
StratoSolar's tether provides a support for fiber optic back-haul links and the platforms can carry very large payloads, both capabilities not possible with station keeping drones or airships. StratoSolar can also station keep at 20km in 50m/s winds.  With these unique benefits in mind its interesting to compare them with the current technical capabilities of drones and airships. 

Titan (Google) and Ascenta (Facebook) drones have serious technical hurdles to overcome. Their first problem is they are only trying to station keep at a max wind speed of 30m/s at 20km altitude. This is insufficient even for India/Pakistan/Bangladesh where the wind speed at 20km can exceed 35m/s. A more realistic max that would cover operations above latitude 30 where it is possible to encounter the wandering polar vortex is 50m/s. Power required increases with velocity cubed, so thats a far off dream.

Their second problem is energy storage. They need to run on batteries for a min of 14 hours during darkness at latitude 30. Each 1KW needs 14kWh of battery storage. LiPo is 200Wh/kg so each KW of power needs 70Kg of storage. The drone engines need about 5KW at 30m/s. Thats 350kg, right at or over the edge of the total mass budget.

Both these problems put the drones in the "not ready for prime time" category. They will work in light winds but won't be able to station keep reliably until better energy storage comes along. Titan's CEO said as much before they were bought by Google.

Darpa pulled development for Boeing's Solar Eagle drone after a couple of years and is now only focusing on developing fuel cells/electrolyzers for energy storage using high pressure hydrogen gas. That reinforces the reality of the energy storage problem.

The Various High altitude airships, including Lockheed's ill fated HALE-D were only trying to meet an inadequate 20m/s spec, but could not even get close to that. Getting sufficient power from the area available for PV panels, and adequate energy storage within the mass budget constrain their operational envelope.

So the contrast is between drones and airships that are real but don't meet station keeping requirements and StratoSolar that can theoretically meet all station keeping requirements, provides unique capabilities but lacks credibility without a practical demonstration.  

By Edmund Kelly

Comments
comments powered by Disqus

    Ed Kelly

    President of StratoSolar

    View my profile on LinkedIn

    Archives

    February 2023
    November 2022
    October 2022
    July 2022
    June 2022
    May 2022
    April 2022
    March 2022
    February 2022
    January 2022
    December 2021
    October 2021
    September 2021
    August 2021
    July 2021
    June 2021
    March 2021
    January 2021
    November 2020
    August 2020
    July 2020
    June 2020
    February 2020
    December 2019
    November 2019
    October 2019
    September 2019
    August 2019
    July 2019
    June 2019
    May 2019
    April 2019
    February 2019
    January 2019
    December 2018
    November 2018
    October 2018
    September 2018
    July 2018
    June 2018
    May 2018
    April 2018
    March 2018
    February 2018
    January 2018
    December 2017
    November 2017
    October 2017
    September 2017
    August 2017
    June 2017
    May 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    September 2016
    August 2016
    July 2016
    June 2016
    April 2016
    February 2016
    January 2016
    December 2015
    November 2015
    October 2015
    September 2015
    August 2015
    July 2015
    June 2015
    May 2015
    April 2015
    March 2015
    February 2015
    January 2015
    December 2014
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    May 2014
    April 2014
    March 2014
    February 2014
    January 2014
    December 2013
    November 2013
    October 2013
    September 2013
    August 2013
    July 2013
    June 2013
    May 2013
    April 2013
    March 2013
    January 2013
    December 2012
    November 2012
    October 2012
    September 2012
    August 2012
    July 2012
    June 2012
    May 2012
    April 2012
    March 2012
    February 2012
    December 2011
    November 2011
    October 2011
    September 2011
    August 2011
    July 2011
    June 2011
    May 2011
    November 2010

    Categories

    All
    All Energy
    Alternative Energy
    Bill Gates
    China
    Clean Energy Investment
    Clean Energy Price
    Desalination
    Developing World
    Energy
    Energy-investment
    Energy Policy
    Germany
    Helium
    Japan Energy Pv
    Land Use
    O3b
    Pv
    PV Bubble
    Pv Subsidies
    Stratosolar
    Us Subsidies
    Wireless Communications

    RSS Feed

 © 2023 StratoSolar Inc. All rights reserved. ​618 S. 8th Street, Suite 400B, Richmond, CA 94804
Contact Us