Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
"Bun is such a sad word, is it not?" -- Watt, "Waiting for Godot"

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UPS Freezer

A battery-backed Freezer... with eco-benefits
  [vote for,

Fridges and freezers are on 24/7. They're often the biggest users of electrical energy in a household. Uninterruptible Power Supplies are baked, mass produced and relatively cheap. This product should have a UPS installed, with about 18 hrs worth of battery. This would offer protection against power cuts, obviously, and also the freezer would run entirely off battery power during the day and take advantage of cheap rate electricity at night.

The government should encourage (perhaps via tax breaks/hikes or whatnot) these. If much of a nation were using them, the increase in electricity baseload and decrease in peak heights would be extremely beneficial to the running of the electricity grid, and concomitant resource consumption/waste production.

In addition, you could perhaps bin the AC motor, go with a brushless DC, which should be slightly more efficient, and would give the advantage of some speed control, perhaps to stop the on-off-on noise which is annoying when you're sitting in absolute silence, the lighting may also be DC LEDs, allowing for all sorts of garish interior lighting schemes...

These should be delivered exclusively by FedEx.

bs0u0155, Aug 22 2012

UK energy demand http://www.national.../Demand/Demand8.htm
[bs0u0155, Aug 23 2012]


       We're sure you've got those efficiency figures for secondary cells at your fingertips …
8th of 7, Aug 22 2012

       Why not just use a eutectic freezer rigged to run off-peak? Get rid of the lossy, expensive electronics.   

       Which is Baked by the way.
Custardguts, Aug 22 2012

       Well, you lose the back up facility. Also, domestic units might not tolerate the loss of volume in a competitive market.
bs0u0155, Aug 23 2012

       I suspect (without bothering to run the numbers) that the ice volume to keep a fridge/freezer at a constant temperature is less than the volume of batteries required. And with a eutectic (phase change) frezer, there isn't any thermal cycling. In addition, you can add back up capacity simply by increasing the ice mass.   

       And of course your approach doesn't have a significant amount of back up if the power goes out at the end of a day cycle.   

       That being said, load side balancing does make sense, but simple day/night cycles aren't nearly effective enough. Smart appliances that can charge/cycle during low load and shut off during high load (with a given minimum on time) make a lot of sense, but need the infrastructure in place to operate.
MechE, Aug 23 2012

       But a eutectic solution will screw up the cold water and ice-maker. Which is a deal breaker, in the US at least.   

       Also, my system's pretty amenable to moment-by- moment load balancing, just add an Ethernet port.
bs0u0155, Aug 23 2012

       so, back of the envelope stuff: I reckon domestic fridges/freezers represent about 2000 MW. Which is roughly the size of our electricity import <link>. The Day/night variation could be softened by about 10% by all the fridges working on my principal...
bs0u0155, Aug 23 2012

       Returning for a moment to our first point…   

       Lead-acid cells are, at best, about 85% efficient. More typically, 75 to 80%; and they have about a 2000 cycle lifetime, depending on the load profile.   

       Do the math; energetically, a minimum of 20% less efficient, plus the cost of powerpack changeout, plus the rolled up (energy, money) cost of cell refurb/recycle, plus the extra overhead (admittedly not much) of the battery management and control.   

       How does that stack up against your notional 10% saving?
8th of 7, Aug 23 2012

       //Do the math//   

       Why is it that Americans only do one math? Surely they can see the advantage that the British have long enjoyed, by doing maths?
MaxwellBuchanan, Aug 23 2012

       //Why is it that Americans only do one math? Surely they can see the advantage that the British have long enjoyed, by doing maths?//   

       Because North Americans are positive and decisive unlike the wishy-washy Brits. They don't need the multiple outs and engineered-in excuses implied by the plural "math(s)" - as if there could be various answers depending upon which math you chose to use. That is why we are AmeriCAN or CANadian while you are merely Brit-ISH.
AusCan531, Aug 24 2012

       Funny: for years I always assumed "maths" was some kind of inside joke at the Halfbakery that I had missed. I guess this is just the only place where I converse with British people about mathematics (unedit: "mathamatics")...
scad mientist, Aug 24 2012

       // mathamatics //   

       … and speleing …
8th of 7, Aug 24 2012

       //… and speleing …//   

       There's never a silent you when required.
AusCan531, Aug 24 2012

       What has mucking around in caves got to do with all this stuff?
neelandan, Aug 24 2012

       [scad] edited the anno …
8th of 7, Aug 24 2012

       /How does that stack up against your notional 10% saving?/   

       It clearly doesn't unless you factor in the 50-75% off peak tarif savings.
bs0u0155, Aug 24 2012

       Fair point. Preumably you are, like the rest of your venal, greedy and selfish species, prepared to sacrifice overall long-term energy conservation for a short-term financial benefit.
8th of 7, Aug 24 2012

       Woith load-side balancing, you will save some energy. The baseload is covered by the most efficient (and usually least-flexible) powerplants. Reducing peak height at the expense of baseload, allows an increased proportion of high efficiency generation. During the day, the UK often has to resort to pumped storage, low efficiency gas turbines or at worst diesel generators. Lower variation would have a knock-on effect to the planning of the grid, also, very clever load balancing might make wind viable.
bs0u0155, Aug 24 2012

       // also, very clever load balancing might make wind viable //   

       If you're talking about your Lower Rear Orifice, yes.   

       Electric Mountain's designed and built to deal with that sort of demand surge. Extrapolating, wind turbines should actually be used to directly drive pumped storage systems - far more efficient than a wind - electricity - pumping - turbine - electricity cycle.   

       Since may wind turbines are marine, they could pump seawater into inland reservoirs at high pressure/low volume and velocity with a fair degree of efficiency, water being fairly incompressible.
8th of 7, Aug 25 2012

       //sacrifice overall long-term energy conservation for a short-term financial benefit.// I might at this point cite the example of the fourth of the Buchanan twins. Denton was extremely happy, atrociously rich and completely un-pensioned right up to the point where the pelota ball hit him. Sturton, the Intercalary and myself raise a glass to his memory several times a day.   

       He was buried, as he requested, at 51°27'17.90N, 2°37'40.33"E. He probably still is.
MaxwellBuchanan, Aug 25 2012

       Anyone who uses the term 'do the math' reveals themselves to require additional education in grammatical matters. This is probably best undertaken prior to engagement with a higher ordered task like mathematics.   

       Of similar grammatical delinquency is the expression: 'write me' when what is meant is: 'write to me'. sighs.... slow learners always require patient teachers. (I'm currently in New York, where they are still waiting for someone to invent the public toilet for them)
xenzag, Aug 26 2012

       Is it not? I only read the annotations, also assuming that it was an idea for refrigerated parcels. Oh dear.
xenzag, Aug 26 2012

       Mathematics is a collective and thus singular noun. While the use of math is a vulgar abbreviation in and of itself, there is no reason for it to retain the 's' from the formal noun. While it is the case that such an abbreviation would be made plural by the addition of an 's' if the original noun was made plural in the same way, this is not such a case.
MechE, Aug 26 2012


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