Cost of making chlorate

People have argued that it costs a lot of money on power bills to make chlorate. The cost is small.
Assume we are going to make one KG of Na Chlorate, thats 9.93 moles. Taking the following figures:

1) One mole NaClO3 = 106.5g.
2) One mole of electrons = one Farad = 26.8 Ah (Ampere hours).
3) It takes 6 electrons to make one molecule of Chloride into one molecule of Chlorate. (2 electrons per Oxygen), that means it takes 26.8 X 6 = 160.8 Ah to make one mole of Na Chlorate (assuming 100% current efficiency, 100% current efficiency means that every electron that goes into the cell will do what we would like it to do, ie. help to 'stick' an Oxygen onto a Chloride).
4) We will assume that we will get 50% current efficiency using a back yard set up with no pH control.
5) Power supply wastes 20% of the power that it delivers, (that's a bad supply).
6) Assume that there is 6 volts across the chlorate cell. There will be no more than this with a sensible cell.
7) Assume the price of power is 8 pence per KWh (kilo watt hour). The KWh is referred to (usually) as a unit of power. Thats approx. 12 cents per unit. It may be different in your area.

We are making 9.4 moles (1kg) of Na Chlorate so we need 9.39 X 160.8 Ah = 1510 Ah of electrons to make 1KG(100% efficiency)
Assuming 50% current efficiency means that it will take twice this, ie. 3020 Ah (Ampere hours).
If we run the cell at 10 amps this means we must run the cell for 302 hours to get one KG of Na Chlorate.
We have 6 volts across the cell so we have a power usage in the cell of 6 V X 10 A = 60 watts.
Assuming that the supply wastes 20% of the power it delivers this means we have 72 watts of power being dissipated in the total set up.
72 WATTS for 302 hours = 21744 watt hours, = 21.744 KWh = 21.744 units.
Assuming that the price of power is 12 cents per unit this means the power cost is 12 X 21.744 = 261 cents ($2.61). (worst possible case)

The voltage across the cell will probably be much less than 6V, and may be as low as 3.6V. The power cost in the States is about 5.5 cents.
The represents a power cost of about 57 cents per KG Na Chlorate produced.

If you can buy Na Chlorate by the barrel it will be cheaper that above but not everybody has access to barrels of Chlorate. The cost above is not the total cost of course you must buy salt (fairly cheap), you must also allow power for boiling/evaporating solutions etc. Chlorate is not expensive to make.