Electricity Model Example

As another example, consider an electricity generation plant, Kuasa Letrik Sdn Bhd. This company generates and supplies electricity to meet the demands of consumers throughout the nation. Kuasa Letrik Sdn Bhd is the oldest power generation and supply company in the country. Throughout the 65 years of its existence, the company has leaped tremendously by continuing adoption of new and efficient generation technologies to meet the ever increasing electricity demand of the growing country. To date it has accumulated a substantial number of plants with diverse fuels and "driver" technologies. The various plant categories cover:

Mini Hydro generation plant
Hydro generation plant
Solar Farm plant
Thermal (Steam) plant
Open Cycle Gas Turbine plant
Combined Cycle plant
Co-Generation plant
Diesel Generator plant

The plant officially runs 24 hours a day, 365 days a year. However, depending on the load or required electricity demand, not all plants are running simultaneously at full capacity. Shutdowns are conducted for both maintenance and statutory inspections by the Federal Machineries Department (FMD), the national inspection and certification authority that ensures all critical plant and equipment like pressure vessels, boilers, furnaces, heat exchangers, etc, are properly maintained for the safe operations.

Brief of the Operations of Kuasa Letrik Sdn Bhd.

Apart from the hydro-electric and solar-electric generation, Kuasa Letrik Sdn Bhd uses 4 types of fuel for its plants :
- piped Natural Gas purchased from Syarikat Gas Asli Sdn Bhd
- liquid Fuel Oil purchased from Syarikat Penapisan Mudah Sdn Bhd.
- liquid Diesel Oil purchased from Syarikat Penapisan Mudah Sdn Bhd.
- solid Coal purchased from Syarikat Arang Batu Sdn Bhd.

Some plants can be fired with more than one type of fuel. The schematic of fuel consumption and electricity generation for the various plants for the company is provided in the diagram below.

The company has enough capacity to supply all the electricity requirements of it customers. It also has the flexibility to program the various "mix operations" of the plants to cater for any shutdown maintainence. The company does not import or export electricity.

The company keeps stock of the liquid fuel in storage tanks and solid fuels in a secured storage yard. The various plants share the supply of fuel from a set of common storage tanks. However, the fuel intake quantities of the various plants are metered separately. For piped natural gas fuel, there is no storage. Consumption of the gas is metered both by the supplier and the company within its premises.

The main output for the company is electricity which is supplied to consumers on a common nationwide supply grid. Kuasa Letrik Sdn Bhd also consumes some of the electricity within its plant for lighting and plant operations. The company also suffers unavoidable electricity losses over the long-distance transmission grids before reaching the customers.

Operational Information

F1 - Stock of Energy Products

Own Consumption means burning the product as fuel in the plant process. Burning to produce electricity is considered conversion.
Conversion means the product is converted to other products including electricity by the plant process.

Product	Own Consumption Qty	Conversion Qty	Unit Qty
NatGas-Thermal-Steam	0	4764889	MMSCF
NatGas-Thermal-OpenCycle	0	518498	MMSCF
NatGas-Thermal-CombinedCycle	0	3003245	MMSCF
NatGas-Cogen	0	511273	MMSCF
FuelOil-Thermal-Steam	0	198511	MTON
FuelOil-Cogen	0	151152	MTON
Diesel-Thermal-UtilitySets	0	123644	MTON
Diesel-Thermal-OpenCycle	0	128749	MTON
Diesel-Cogen	0	299343	MTON
Coal-Thermal-Steam	0	504094	MTON

F4 - Sales of Energy Products by Distribution Channels

Products	Sales End User	Sales Reseller	Sales Bunker	Sales Intercompany	Sales Foreign Exports	Unit Qty
NatGas-Thermal-Steam	0	0	0	0	0	MMSCF
NatGas-Thermal-OpenCycle	0	0	0	0	0	MMSCF
NatGas-Thermal-CombinedCycle	0	0	0	0	0	MMSCF
NatGas-Cogen	0	0	0	0	0	MMSCF
FuelOil-Thermal-Steam	0	0	0	0	0	MTON
FuelOil-Cogen	0	0	0	0	0	MTON
Diesel-Thermal-UtilitySets	0	0	0	0	0	MTON
Diesel-Thermal-OpenCycle	0	0	0	0	0	MTON
Diesel-Cogen	0	0	0	0	0	MTON
Coal-Thermal-Steam	0	0	0	0	0	MTON

F5 - Losses of Energy Products

Products	Losses Flaring	Losses Storage	Losses Operation	Losses Transportation	Losses Other	Unit Qty
NatGas-Thermal-Steam	0	0	276366	0	161449	MMSCF
NatGas-Thermal-OpenCycle	0	0	0	0	0	MMSCF
NatGas-Thermal-CombinedCycle	0	0	0	0	0	MMSCF
NatGas-Cogen	0	0	0	0	0	MMSCF
FuelOil-Thermal-Steam	0	6880	4218	0	2581	MTON
FuelOil-Cogen	0	0	0	0	0	MTON
Diesel-Thermal-UtilitySets	0	8918	0	0	1805	MTON
Diesel-Thermal-OpenCycle	0	0	0	0	0	MTON
Diesel-Cogen	0	0	0	0	0	MTON
Coal-Thermal-Steam	0	0	15601	0	0	MTON

The MEDiS Balance Model for Kuasa Letrik Sdn Bhd.

The input forms F1, F2, F3, F4 and F5 as shown above are provided as web based online inputs to the data provided for MEDiS.

Access to the above forms is only possible with authentication, login name and password. The result of the submission of those forms is a combined or assembled table shown below. Every submitted value is captured in the the table. The table calculates the sum of all the inputs and the sum of all the outputs on a row by row basis. The result of the calculation is provided in the rightmost column of each row.

As we can see on the right most column, the value of "NET BALANCE" is zero. This is the case for the set of data submitted that is fully balanced. Otherwise the data provider will have to go back to the respective forms, modify and resubmit the necessary inputs until the "NET BALANCE" values are all zero. This is the condition required for Balance in the MEDiS model.

MEDiS Model for an Electricity Generation Plant

The Company

Brief of the Operations of Kuasa Letrik Sdn Bhd.

Operational Information

F1 - Stock of Energy Products