>50W/inch^3 is soldering iron level heat dissipation ...we'll 50W/inch^3 is the throughput. If you assume 96% efficiency (which is common for COTS inverters),

>50W/inch^3 is soldering iron level heat dissipation ...we'll 50W/inch^3 is the throughput. If you assume 96% efficiency (which is common for COTS inverters), you'd have 2W/in^3 in waste heat to dissipate. And 50W/in^3 isn't very high on just a per-piece level. Here's a Vicor DC/DC converter that has 1240W/in^3 power density: http://www.vicorpower.com/promotions/AC_to_PoL/ChiP_Technology/DCM/lp.php http://www.vicorpower.com/promotions/AC_to_PoL/ChiP_Technolo... ...of course getting rid of the parasitic heat isn't included in that example. > Which is to say to take something which is 90% efficient and make it 99% efficient. 99% efficient isn't completely unheard of: http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=377536&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D377536 http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=377536... ...to me it seems like the catch is FCC Part 15 B compliance. That seems like that'll be the biggest thing to disqualify smaller entries.