convert = function(orig_csv_file, nb_series_per_chunk)
{
	orig_file = file(orig_csv_file, open="r")
	ignored = readLines(orig_file, 1) #skip header

	serie_length = 17520 #365*24*2
	library(sqldf, quietly=TRUE)
	ids = read.csv.sql(file_csv, header = TRUE, sep = ","
		sql = "select * from file_csv group by FK_CCU_ID")
	index = 0
	repeat
	{
		if (index+1 >= length(ids))
			break
		request = "select CPP_DATE_PUISSANCE,CPP_PUISSANCE_BRUTE where FK_CCU_ID in ("
		for (id in ids[index + seq_len(nb_series_per_chunk)])
			request = paste(request, id, ",", sep="")
		request = paste(request, ") order by FK_CCU_ID,CPP_DATE_PUISSANCE", sep="")
		series_chunk = read.csv.sql(file_csv, header = TRUE, sep = ",", sql = request)
		
		index = index + 17520