Abdul Rehim, J:

1. Petitioner in the writ petition is the appellant herein and the respondents are the respondents. Three distinct issues were agitated in the writ petition. First issue was regarding correctness of Ext.P13 and P15, demands for payment of arrears of electricity charges, for the period from April, 1990 to June 2004, calculated at Rs.11,48,952/-. The said amount was demanded as a back assessment alleging non-installation of TOD Meter (Two-part Electric Meter). The appellant was an LT consumer with a connected load above 100 KVA, which is coming under the category known as "deemed HT". By virtue of a circular issued by the respondent Board dated 20-11-1989, it was instructed to calculate the demand charges with respect to such consumers at 75% of the connected load, till the two-part meters are installed. Several educational institutions represented before the Board that since all the machineries installed are not used simultaneously and since most of the machineries are idling, maximum demand will be very low and hence the demand charges if taken as 75% of the connected load they will become compelled to make payment of very high amount than what will be due on the basis of actual consumption. The Board in Ext.P1 circular issued instructions to its officials that, as a special case the educational institutions having connected load above 100 KVA and availing supply at LT, shall be billed from 3/89 onwards till the two-part tariff meters are installed and HT agreements are executed, at 50 KVA on a provisional basis, subject to condition of them executing an undertaking to the effect that additional amounts if any based on actual recorded maximum demand and 75% of the contract demand will be paid as and when they install the two-part tariff meters.

2. In the case of the appellant the two-part meter was installed only in 5/2004. Thereafter taking average of the maximum demand for the months of June, July and August 2004 a back assessment was made calculating the difference between the average MD and the 50KVA, for the periods from 4/1990 to 6/2004. The appellant raised contentions that on 11-12-1991 they have purchased a two- part meter as per Ext.P17 and it has got tested by the TMR unit of the Board. But inspite of requests made, the Board has failed to install the Meter and the position continued as such despite reminders. A two-part meter was installed by the Board on 02-03-2002. But in May 2003 the Meter was found to be defective. Subsequently the appellant was requested to install a two part Meter through Ext.P7 notice issued on 13-07-2005. The appellant's case is that, once the Board has installed a two-part meter in March, 2002 adoption of the average consumption for the months of June, July and August, 2004 for the purpose of calculating the arrears is erroneous. Against Ext.P13 the appellant submitted objections as per Ext.P14. The Board re-considered the matter and issued Ext.P15 demanding a total sum of Rs.12,82,564/- including Rs.35,750/- towards short assessment of minimum demand for the period from March 1989 to March 1990 and Rs.95,927/- towards 25% of the energy charges levied as penalty for non-installation of TOD meter for the period from May 2004 to November 2004.

3. Challenging Exts.P13 & P15 it is contended that, during the period between 1990 and 2004 there was considerable increase in the consumption due to various expansions and modernisation and therefore average consumption of the months of June, July and August 2004 adopted for the purpose of billing for the periods from 1990 onwards is not real and true. Further it is contended that, since there was failure on the part of the authorities of the Board in not installing the Meter which was purchased as early as in the year 1991, such a back assessment made with inordinate and unreasonable delay cannot be sustained.

4. The above contentions of the appellant were resisted on behalf of respondent Board by denying the allegation tha