17 May 2009

Different, better ’fridges

When designing (RAPS) remote area power systems (which gains new importance when considering a US financial expert’s recent advice on LateLine: “Now is the time to get a farm & a gun.”), the single biggest load is invariably refrigeration (often more than half of the entire demand).

UK researchers have discovered new properties of magnetic refrigeration cores which are typically 20-30% more efficient than traditional adiabatic methods.

On top of this, the development of a “spin battery,” which captures energy using Magnetic Tunnel Junction devices — which can be built precisely enough to potentially replace computer hard drives — may have decimated the single most expensive & difficult-to-manage (& heaviest) component of a RAPS.

There are a number of other developments in wind-power systems (particularly the rotors, implying that these improvements require no changes to or replacement of generators or towers) which hint that a distributed (“community”) apporach to energy may prove to be much more efficient & robust than today’s massive fossil-fueled generators & extensive power grids.


Anonymous said...

A battery is the wrong way to go.

Best to have some large blocks of a material that changes phase at the right temperature. During the day use solar power to cool something that freezes at 5C in the fridge and something that freezes at -20C in the freezer. Overnight they will melt and suck enough thermal energy to keep all your food cold while you have midnight snacks.

I believe that such fridges are already on sale.

Russell Coker

Leon RJ Brooks said...

Hi, Russell...

Apparently the spin “battery” is efficient enough to render phase-conversion methods a bit cumbersome.

Thinking of it as being a magnetic capacitor (not a complicated chemical storage cell), may help.

Leon RJ Brooks said...

The phase-conversion method done the way you describe, I might call “stealth technology” as it overtly looks simple, yet choosing the components (including stretchable containers if one includes water) can be quite complex.