Don't know if the OP was from the UK, but UK night rates are of the
order of half the day rate (though you have to pay a higher day rate to
qualify!), but only for 7 hours. I do wonder if it would be possible
now to set up a battery/inverter/load sharing system sufficiently
cheaply to lower the cost of daytime use significantly. Probably
illegal though.
================================
Why would it be illegal storing energy ? I can't imagine that it is
illegal charging the batteries of a Golf buggy , at night tariff.
I am sure any golf club would do that to reduce their electricity bill.

BTW ,living in the UK myself ,night tariff indeed normally starts at
about 2300 hrs and finishes at 0600 hrs the following morning .
At our place switching happens with an electro-mechanical timer with a
spring mechanism such that following an outage the timer keeps running.
Eventually that spring has to be re-wound by the electricity supplier
,but that hasn't happened the past 15 years........so the timer at our
place now comes into operation around 2320 hrs ,but then of course also
day tariff starts about half an hour later at 0620 the following morning.

Frank GM0CSZ / KN6WH

Highland Ham wrote in
:

Don't know if the OP was from the UK, but UK night rates are of
the order of half the day rate (though you have to pay a higher
day rate to qualify!), but only for 7 hours. I do wonder if it
would be possible now to set up a battery/inverter/load sharing
system sufficiently cheaply to lower the cost of daytime use
significantly. Probably illegal though.
================================
Why would it be illegal storing energy ?

No problem with a different circuit, but more so if you want to
connect to the supply. In fact people with wind etc. generators can
get permission to sell "green" electricity back to the grid
(automatic metering). It would be somehow satisfying buying night
time electricity from the suppliers and sell it back to them at a
profit.

I can't imagine that it
is illegal charging the batteries of a Golf buggy , at night
tariff. I am sure any golf club would do that to reduce their
electricity bill.

BTW ,living in the UK myself ,night tariff indeed normally starts
at about 2300 hrs and finishes at 0600 hrs the following morning .
At our place switching happens with an electro-mechanical timer
with a spring mechanism such that following an outage the timer
keeps running. Eventually that spring has to be re-wound by the
electricity supplier ,but that hasn't happened the past 15
years........so the timer at our place now comes into operation
around 2320 hrs ,but then of course also day tariff starts about
half an hour later at 0620 the following morning.

Just to get back on topic (nearly), my meter is controlled from a
radio signal (?198kHz) which can move the 7 hours about within a
longer window.



--
Percy Picacity

No problem with a different circuit, but more so if you want to
connect to the supply. In fact people with wind etc. generators can
get permission to sell "green" electricity back to the grid
(automatic metering). It would be somehow satisfying buying night
time electricity from the suppliers and sell it back to them at a
profit.

How is that arranged? I presume the windmills produce DC?

Or if AC how do they arrange synchronisation with the
mains?
===============================
Domestic wind energy systems in the 1-10 kW range often involve an AC
generator ,its output being rectified with the DC fed into an inverter
which is synchronised with the grid.

In the UK a company 'Windsave' sells and (obligatory) installs 1 kW wind
generators which are connected to the domestic 230V-50 Hz system .
The location of the windgen and its nearby inverter cannot be too far
away from the switchboard (up to 15 metres). Apparently the output
voltage of the inverter is slightly higher than the grid supply , such
there is a preferential pick-off from the wind gen system.
However when no power is consumed wind generated energy is fed into the
grid.
I have 'heard' that in some countries (but not in the UK)
electro-mechanical kiloWattHour meters can rotate reversed when fed
with power from the consumer's side, with the counter counting down .
This would be very beneficial for people with the above described system
.. Perhaps someone on this NG can confirm that these meters really exist
and in which countries.

For my AR operations + desk lighting and peripherals I use 12 V
batteries charged by an up to 170 Watts windgen and 2 solar panels with
a total capacity of 128 Watts(peak)............just for the h*ll of it.
The wind gen. has a 3 phase generator and integral rectifying diodes( in
fact 2 bridge rectifiers of which 1 is fully utilised and the other one
only half )

Frank GM0CSZ / KN6WH The future is 'renewable'

Hi Frank and all,

I have 'heard' that in some countries (but not in the UK)
electro-mechanical kiloWattHour meters can rotate reversed when fed
I have never seen a reversible mechanical kWh meter and also never heared of
this, except running reverse due to incorrect wiring.

In our current home (IJmuiden, NL) we have an electronic 3-phase meter with
two counters for peak and off-peak. This meter also has a T3 to measure
energy supplied back into the net, though that requires a special contract.
It's a single LCD showing the counters sequentially.
I know the previously used electro mechanical meter in this house was
switched by a 230Vac signal on an extra wire in the mains cable. I'm prety
sure there are two 1.5 or 2.5 qmm wires with the four 6 or maybe 4 qmm wires
in the cable.
There still is an old boiler relay on the meter board controlled from the
same signal.
The new electronic meter might be frequency controlled.

In the previous home we did have an electro mechanical two-tarif meter and I
think that one was switched from an electronic unit that I presume was a
frequency selective relay.

The meter back in Newbury was just the standard single phase, single counter
type.


I would expect that all modern wind turbines use rectifiers direct on the
generator and then have DC power fed to one or more inverters in the base of
the mast.
The inverters are synchronised to the grid before switching the generator on
the net.
This is as I remember from college and as I read in the technical
description of the wind turbine on which PI3WAD is installed.


Angela
M1SCH / PE1BIV

Brian Morrison writes:
I think that the generator is driven by a constant speed drive, the
blade angle being used to control the speed of this drive, and the
output connection (relays perhaps) is not closed until the drive has
been frequency and phase matched with the grid connections. This is
pretty much how a conventional power station does it.


Only on VERY LARGE wind farms. Most small sites rectify the wild AC
and use syncronous inverters to feed back into the grid.

--
Lawrence Statton - m s/aba/c/g
Computer software consists of only two components: ones and
zeros, in roughly equal proportions. All that is required is to
place them into the correct order.