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UPS Freezer
A battery-backed Freezer... with eco-benefits | |
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.
UK energy demand
http://www.national.../Demand/Demand8.htm [bs0u0155, Aug 23 2012]
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Annotation:
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We're sure you've got those efficiency figures
for secondary cells at your fingertips
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Why not just use a eutectic freezer rigged to run off-peak? Get rid of the lossy, expensive electronics. |
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Which is Baked by the way. |
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Well, you lose the back up facility. Also, domestic
units might not tolerate the loss of volume in a
competitive market. |
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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. |
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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. |
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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. |
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But a eutectic solution will screw up the cold water
and ice-maker. Which is a deal breaker, in the US at
least. |
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Also, my system's pretty amenable to moment-by-
moment load balancing, just add an Ethernet port. |
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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... |
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Returning for a moment to our first point
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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. |
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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. |
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How does that stack up against your notional
10% saving? |
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Why is it that Americans only do one math? Surely
they can see the advantage that the British have
long enjoyed, by doing maths? |
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//Why is it that Americans only do one math? Surely they can see the advantage that the British have long enjoyed, by doing maths?// |
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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. |
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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")... |
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There's never a silent you when required. |
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What has mucking around in caves got to do with all this stuff? |
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/How does that stack up against your notional 10%
saving?/ |
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It clearly doesn't unless you factor in the 50-75% off
peak tarif savings. |
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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. |
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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. |
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// also, very clever load balancing might make wind viable // |
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If you're talking about your Lower Rear Orifice, yes. |
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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. |
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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. |
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//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. |
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He was buried, as he requested, at 51°27'17.90N,
2°37'40.33"E. He probably still is. |
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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. |
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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) |
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Is it not? I only read the annotations, also assuming that it
was an idea for refrigerated parcels. Oh dear. |
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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. |
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