Sorry folks but this advice is kind of obsolete post-Tekkit as charging benches have been nerfed pretty badly and as far as I know the transformer upgrade trick no longer works.
With IC2 Experimental (or at least the version in FTB:Monster) it ignores EU levels but I understand that when it stops being "Experimental" the miner's level will be 128EU/t. This means it can be powered from a CESU which is like an improved batbox. The CESU appears to retain charge on wrenching, also an "advanced batpack" (same tier) holds more than the CESU.
The "Advanced miner" is different, if you put in transformer upgrades (2 I think) you can put a lapotron in its power slot. So far I've got to 36 overclockers without power problems.
Gregtech Lappacks appear to be the same tier as re-batteries and therefore able to power a miner, but post-GT the options are either lots of batpacks, a generator of some kind, or placing the appropriate transformers to transform higher-tier power down.
I figured this out while I was using a "miner" as it needs EU power and once its finished you need to move everything and start again, so a generator setup is a PITA (unless you have access to Dartcraft LOL)
My TEKKIT solution (obsolete (damn I miss Tekkit)):
Charging bench Mk.1
Charging bench Mk.3
2*Transformer upgrades
Lapotron crystal (Or an energy crystal but its only a tenth the power)
Redstone torch
Put the Mk.3 bench somewhere that receives power then use it to charge the lapotron. Its a HV device but it will accept lower voltages, though be careful where you put it (if it receives a redstone signal it may output HV, destroying adjacent machines).
Put the Mk.1 where you want power (make sure it really is a MK1), put the lapotron and 2 transformer upgrades in and put the redstone torch next to it so it becomes a "discharging bench". The transformer upgrades allow it to discharge the lapo to LV, so it won't blow up basic machines. Note that storage devices won't blow up the bench, without the upgrade it just does nothing.
Automatic mining using the charging benchOK the full kit for this was:
1:Miner
1:Pump (the pump is optional but means the miner can work through water and lava)
1:OV Scanner
1:Diamond drill bit
64:drill pipe
Some empty cells (for the pump)
1:Charging bench MK.1
1:Insulated copper cable (for the pump)
2:Transformer upgrades
1:Charged lapotron
2:Wooden chests
1:Lever or redstone torch
Place the miner
Place the pump alongside
Place the bench behind the miner
Place the wire behind the pump
Put the chest in front of the pump and miner
OPTIONAL you may want to load the bit and a few sections of pipe first so it digs straight down a short distance before branching sideways. On dirt or stone 1-2 sections will prevent the ground vanishing under your feet. On sand 5-10 may be advisable?
Load the bit, pipe and scanner into the miner
Load the cells into the pump
Load the lapotron and transformer upgrades into the bench
Apply redstone to the bench
Wait
Note that if there is ore on the surface then the ground may start vanishing, so grab some cobble from the chest and fill it in.
The miner is finished when its power indicator stays full (no longer drilling) no more material appears in the chest or the noise ceases.
If the miner runs out of drill pipe you can add more. Generally you won't need this in overworld but if you start high enough you might. Nether boreholes can easily exceed 64 deep.
Remember when you finish to dismantle it in the correct order:
Take the unused pipe out of the miner
OPTIONALLY you can put backfill material in the slot where the pipe went. This can be very useful for exploring caverns. Further you can backfill with ladders, by default they stick on the south side of the shaft (facing north).
Take the bit and scanner out of the miner
Take any unused cells out of the pump
Drill pipe will appear in the chest, wait for it to finish. If you are backfilling a bore deeper than 64 you will need to keep topping up the backfill supply.
OPTIONAL borehole capping method if you are not backfilling: put 2 bits of drill pipe and the drill bit back, then put 2 bits of dirt or stone in and remove the bit. Result is a short cap on the borehole.
Take the lapotron and upgrades out of the bench.
Empty and clear the chest.
Dig in front of the miner and block up the drill hole (not needed if you backfill or cap it).
Dismantle the remaining equipment.
Big don'ts are:
1 Don't dismantle the chest too early or stuff will be spat out as entities
2 Don't dismantle the miner too early or it will leave the drill pipe behind in the hole.
3 Don't forget to block up the hole or you may find equipment falls down it, sometimes irretrievably.
4 Don't use the wrong tool, a normal wrench is enough though.
5 Don't set it up on visible ore or you'll be left with nothing to stand on, build a little platform if needed.
6 If you try this in the old Tekkit in the nether the ores WILL explode, in a big way.
Running a miner with diamond bit, OV scanner and pump all the way to bedrock took roughly half the charge in the lapotron.
When you've finished the
bench can be removed with a regular wrench or even a pick or drill, as unlike generators it won't break to a machine block (I think you lose it if broken by hand). Its not a storage device so you don't waste energy when you move it (OK It holds a trivial amount, less than a re-battery).
Incidentally the miner doesn't appear to need a lossless wrench either, a regular wrench should do.
Charging bench and energy link powering a pumpAn interesting thing happened when I combined the charging bench with an energy link and a buildcraft pump. Now as you are well aware the buildcraft pump is capable of epic feats of drainage if given sufficient power, but in buildcraft this normally means the highest level of engine, the IC-engine, which needs fuel and cooling, and can blow up.
New setup:
1 re-battery (OK I had to recharge it ... once) in a MK.3 charging bench with redstone applied ->energy link->buildcraft pump->3 geo generators->MK.3 charging bench with four empty lapotrons
Oops where did that lava lake go
P.S.
You can add waterproof cobblestone pipe between the buildcraft pump and a geothermal generator. The pump does NOT need a wooden pipe to extract lava, and liquid pipes do NOT drop items.