75% Efficiency From Induction Electrification of Roadbeds

  Since battery costs are 2X grid costs, even 33% efficiency would be
competitive with charging stations.

~~~~~~~~~~~~~~~~~~~

http://en.wikipedia.org/wiki/Wireless_energy_transfer#Size.2C_distance_and_efficiency


Wireless electric energy transfer for experimentally powering electric
automobiles and buses is a higher power application (>10kW) of
resonant inductive energy transfer. High power levels are required for
rapid recharging and high energy transfer efficiency is required both
for operational economy and to avoid negative environmental impact of
the system. An experimental electrified roadway test track built circa
1990 achieved 80% energy efficiency while recharging the battery of a
prototype bus at a specially equipped bus stop <SUP class=reference
id=cite_ref-17>[18] <SUP class=reference id=cite_ref-18>[19]. The bus
could be outfitted with a retractable receiving coil for greater coil
clearance when moving. The gap between the transmit and receive coils
was designed to be less than 10 cm when powered. In addition to buses
the use of wireless transfer has been investigated for recharging
electric automobiles in parking spots and garages as well.

Some of these wireless resonant inductive devices operate at low
milliwatt power levels and are battery powered. Others operate at
higher kilowatt power levels. Current implantable medical and road
electrification device designs achieve more than 75% transfer
efficiency at an operating distance between the transmit and receive
coils of less than 10 cm.

~~~~~~~~~~~~~

Any pot holes deeper than 10 cm are "shovel ready" projects.


Bret Cahill

 On Wed, 31 Dec 2008 11:47:10 -0800 (PST), Bret Cahill


                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^



Doesn't sound like they were charging a moving vehicle. If it's
stopped, why not used a connector, and get 100% transfer efficiency?

John

 

John Larkin wrote:


Rain, mud, ice, sleet, snow, vehicular damage, vandalism come to mind as a few
possible
reasons.

Graham

 
Do you see any problems with a moving version?  Not that it would
necessarily be cost effective but of anything in thermo or fields that
would make it impossible or very difficult?


For that matter why not just put a couple rails in the pavement like
subways?  A vac truck could come by every so often to keep trash from
shorting it out.  In heavy downpours, ice or snow you burn fuel.

The consumer society was pre peak.  We need to adapt to a survival
society.  Kids shouldn't be playing in interstate traffic anyway.


Bret Cahill

 

Bret_E_Cahill@yahoo.com wrote:


YES ! VAST problems. Basic to physics which you clearly have never understood,
so it's largely pointless trying to explain why.

Graham