TECHNOLOGY

Dorad has invested in setting up computer systems that are among the most advanced in the world for forecasting and billing.

HOW IT WORKS

FROM PRODUCTION TO SWITCHING ON THE LIGHT

Dorad has sold the electricity it produces to end customers, which include public, business, or commercial entities nationwide. The power is supplied to these customers via the national power grid, in exactly the same way they receive power today, with Dorad making any excess capacity at any given half hour available to the system manager.

The private electricity market requires Dorad to produce at any given half hourly period the precise amount of electricity that our customers will use in practice, plus any additional capacity that may be requested by the system manager. To this end, Dorad builds aggregated half-hour usage forecasts for all our customers, to which we add the production capacity required by the system manager in order to generate the daily production plan accordingly.

Dorad produces and supplies electricity in accordance with these precise half-hourly plans to the national electricity grid, which is a natural monopoly of the Israel Electric Corporation (IEC), receiving electricity from all the power stations around the country and supplying it to the entire population of the State of Israel.

The accounting vis-à-vis the system manager is measured on a half hourly basis, as the difference between the actual consumption of electricity by our customers and the energy that we produced and transmitted to the grid.

Dorad has invested in setting up computer systems that are among the most advanced in the world for forecasting and billing. These systems make it possible to manage meter readings and to issue invoices at reduced tariffs, according to the contracts signed with customers, to manage the consumption forecast for each customer, at the half hour level, according to the standards set by the Public Utility Authority – Electricity, to manage the gas contract with the gas supplier and with Israel National Gas Lines Ltd (INGL), and to conduct the daily administration vis-à-vis the system manager in determining the half-hourly consumption plans submitted thereto in advance on a daily basis, while meeting the precision and calculation methodology in accordance with the standards.

STATION STRUCTURE

Dorad’s power plant is expected to deliver more than 800 Megawatts to the electricity grid, amounting to approximately 7% of the total production capacity in all of Israel, plus an additional 40 Megawatts for use by the company.

The station consists of two blocks, each of which includes six gas turbines, six waste heat boilers, and one steam turbine. In order to reach maximum fuel efficiency, each gas turbine passes the residual heat in its emission gases through the waste heat boiler (Once-Through Steam Generator – OTSG), which serves as a heat exchanger exploiting the temperature of the hot exhaust gases.

Natural gas burners, located in the transition ducts leading from the gas turbine to the boiler, can be fired during peak hours to further heat the gases emitted from the gas turbine in order to increase the steam production, thereby increasing the capacity of the steam turbines (an addition of approximately 60 Megawatts for each block), allowing them to reach an output of 140 Megawatts for each.

In total, Dorad will be able to produce approximately 420 Megawatts in each block, at a combined-cycle efficiency of around 51% (when not using duct firing).

The LM6000 aeroderivative gas turbines, each with a capacity of approximately 48 Megawatts, were manufactured by General Electric (GE) in its plant in the U.S., and packaged at the GE facility in Hungary. These turbines, manufactured to aviation standards, underwent rigorous testing at the assembly plant before being shipped to Israel.

The SKODA MTD-40 steam turbines are capable of producing approximately 140 Megawatts apiece, and each is connected to a generator produced by Brush.

The balance of plant includes a seawater cooling tower, which supplies the condensers and the rest of the plant, and a water treatment plant that produces extremely high quality feedwater for boiler make-up, injection into the gas turbines (for NOx reduction and SPRINT power boosting), and cooling of turbine inlet air on hot days. The plant is highly automated and controlled from the central control room by a Rockwell control system that interfaces with the controllers supplied by the individual equipment suppliers.

There are significant advantages to Dorad’s configuration, not least its great operational flexibility and reliability. The turbines have dual fuel capability, so that they can be powered by either natural gas or by diesel oil as backup.

The turbines’ versatility is expressed too in their ability to synchronize with the electricity grid within two minutes of initial startup, and to reach full load in less than 10 minutes in total.

The modular structure of the LM6000 gas turbine, which allows for fast swap out of complete assemblies, means that should any internal failure occur in the turbine, it will not significantly impact the production capacity of the station, and it can be repaired and returned to service within about five days – including replacement with another gas turbine if necessary.

This unique configuration, with a multitude of smaller units, ensures maximum efficiency even during partial loads. Dorad can therefore turn on or switch off units according to the required load: instead of operating larger turbines at partial loads – which means that each unit will be operated close to its full load over the entire range of operation. This operating flexibility will also greatly contribute to the overall reliability of the country’s electricity grid.

In general, this configuration, in combination with the computerized electricity management system, will also allow Dorad to cope with regulatory and market changes which are likely to vary, until such time as this competitive market, which is still in its early infancy, reaches maturity and stability.