Application Of Tariff System To Reduced Energy Bills
(a) Time of use metering :
- The time of use metering (TOU) involves dividing the day, month and year into tariff slots.
- Energy used during peak load periods is charged at high rates and that used during off peak loud period charged at low rates.
- It affects on consumers to use less energy during peak load and more during off peak loads, which results automic load control during peak load period.
- As the load demand is controlled, the supply agency can plan for their generation and transition infrastructure approximately
(b) Domestic usage meter :
- Domestic variable rate meters allowing two tariffs i.e. ‘Peak’ loud and off peak load can be used to domestic consumers.
- It will induce domestic consumers also to use power during off peaks loads and reduce their demand during peak-load to achieve saving in energy bits reducing load demand.
- Such installation use simple electromechanical switch they are used in conjunction with electrical storage heaters.
(c) Getting benefit by improving energy efficiency :
- Consumers may install power factor correcting devices at their premises or installations to achieve benefits of higher power factor as per tariff. Which will reduce load current demand .
- H.T. consumers are induced to use energy at high load factors so that plant capacity is best used and energy cost of generation is reduced.
(d) Energy conservation by improving load factor :
- Load factor is defined as kWh delivered to a system in a particular period of time to total possible time to that could be delivered by the system in the same designated period of time. Depending upon these period, the load factor may be called as daily, monthly or yearly etc. The value of this factor is always less than one.
- When the load factor is improved, means made nearer to one, means for same maximum demand number of units used are more or number of units generated are more, which reduces cost of generation per unit.
- The generation plant can operate its generating sets in such a manner, that their usage is constant and no peaks or valleys exist in the load curve it will achieve a load factor of unity.
- Consumers should be offered at low rates if they use energy during off peak loads, so that load factor will be improved, reducing cost of energy generated . The cost of labour per kWh of energy genera decreases as number of units generated increases because the labour cost remains the same, irrespective e working of alternator at 25%, 50% or 100% load factor.
- Load factor can also be improved by reducing maximum demand on the plant.
- Load factor can also be improved by increasing production efficiency that is reducing losses in system.
- Load factor of the system can also be improved by making different consumers to shift their maximum demands during different hours of the days.
- It can be improved by installing energy management systems.
- Maximum use of energy can be obtained by lowering peak demands along with keeping demand stable.
(e) Advantages and Economy achieved by Improvement of power factor :
It is always beneficial to both supplier as well as user of electricity to use power or supply it at higher power factor, because :
- Load in kW supplied is increased hence capacity of prime movers as well as kW capacity of the generating plant is better utilized or its kW capacity increases.
- kW capacity of the transformers as well as transmission and distribution lines increases.
- Efficiency of every plant increases.
- Cost of generation is reduced, hence energy charges are less.
- Due to improved p.f. current required to supply the same kW load is reduced, hence voltage drop is reduced, improving the regulation of lines and alternator.