|Cost of UST_1 stellarator|
Abstract : The cost of each system in UST_1 and some particular elements is tabulated. Some prices are unknown because the elements were loaned or offered free. The total cost of materials for the vacuum vessel, coil grooves, windings and power supplies is 350 and the cost of the vacuum system 1600 .
Table of costs
Meaning of columns:
nş : number of units of the product
Unit price : the cost per unit
Total : Cost of the product including transport cost from the origin to Spain and in case, import taxes and charges.
Meanings in the table:
used = second hand, used or surplus element.
repaired = the item did not work when received and was repaired in-site. These items are very low cost ebay items without warranty.
Transp. = transport
* The transport cost of some ebay items, usually coming from Germany, UK, USA and even from Singapour is higher than the item itself.
* Some elements were free mechanised by some companies, for example 6 flanges for the vacuum system, welding the pieces for the mechanising device, mechanising of the main ring for the same device. It is not accounted. The proportion of these elements is not important so the error is not significant.
* Other free offered elements are included in the table at the commercial approximate cost.
* I personally cut and mechanised many small and simple pieces for the mechanising device. It is not accounted.
* The vaccum system is the most expensive one. Many of the costly vacuum elements are ebay second hand items, usually 5 or even 10 times cheaper than new elements. The normal cost for this system could perfectly be 15000 or 30000. The cost of the present system is only 1600 but it has more breakdowns and the quality of the mechanical pump is too low.
* The time spent in the study, design, commissioning, purchases, assembling, tests, start-up of UST_1 is not included. It has been accounted in a database and it will be analysed. However each hour could be hypothetically paid at 60/hour for an average engineer or at 6/hour for a low income worker. In any case the cost of work will be high because more than 2000 hours have been spent.
* The total expenditure from accounts is 3700. The total assigned to particular systems is 2678, so ~1000 was the inversion to improve the laboratory including: new tools and machinery, measuring devices, electronic and mechanical components, glues, materials, cleaning solvents, etc.
* The high vacuum pump in the vacuum system is very powerful (~150 L/s) so the vacuum system might be used for a bigger stellarator, perhaps 3 times larger.
* The cost of a stellarator 3 times larger, made using the same philosophy, named UST_2, will be estimated soon.
I thank to the companies and individuals that lend or offered many elements, manufacturing process or information by free. They contribute to reduce the real expenditure and to speed up the building process of UST_1.
Date of publication 26-08-2006.