tag:blogger.com,1999:blog-6156940350159100953.post4866732336270092528..comments2024-01-14T22:07:22.183-08:00Comments on Sustainable Energy - without the hot air: 2014 Longitude Prize Flight ChallengeDavid MacKay FRShttp://www.blogger.com/profile/08023079754784119955noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-6156940350159100953.post-66263281877495916932014-07-28T06:46:52.924-07:002014-07-28T06:46:52.924-07:00I have a lot of sympathy for Anonymous's sugge...I have a lot of sympathy for Anonymous's suggestion to "not get excited about blimps/airships/LAVs" - I wrote about <a href="http://www.withouthotair.com/cC/page_280.shtml" rel="nofollow">airships in the Flight II chapter of my book</a>. The energy challenge for an airship is indeed significant - it is like adding a huge advertising to the roof of an ordinary truck. But I think it is worth being open-minded (just a little bit!). The longer the airship is, the better the energy situation. Moreover, the surface of the airship is a handy place to put solar panels when they are cheap enough. I reckon that big enough (long enough) airships covered with solar panels might be a credible solution for zero carbon freight transport. I'll write a blog post with the analysis when I get the chance. David MacKay FRShttps://www.blogger.com/profile/08023079754784119955noreply@blogger.comtag:blogger.com,1999:blog-6156940350159100953.post-6215974390425527282014-06-25T06:52:49.663-07:002014-06-25T06:52:49.663-07:00Don't waste any time getting excited about lig...Don't waste any time getting excited about lighter-than-air-vehicles (LAVs). An American aeronautical engineer, Joseph Dick, has demonstrated quite conclusively that LAVs, especially hybrids, are fundamentally lousy in energy efficiency compared to other forms of transport (helicopters excepted - maybe). Even jet transports use less fuel per ton-mile as well as being much faster. Just google 'helium hokum'.Anonymousnoreply@blogger.com