An industrial facility has an old boiler that consumes 20 MW with 8% excess ar, and...

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An industrial facility has an old boiler that consumes 20 MW with 8% excess ar, and the stack temperature rise (STR) is 360°C. The boiler consumes natural gas whose heating value is 54 MJ/kg. The cost of natural gas is SR 1.1/kg. The facility also has a compressed air system that provides air at a pressure of 8 bar and consumes 1,500 kW continuously throughout the year. The facility needs hot water and it is provided by electric water heaters that consume 250 kW continuously throughout the year. The facility owner would like to reduce energy consumption by hiring an ESCO on a 10-year shared savings contract, where the ESCO receives annual payments equal to 50% of the annual savings. The ESCO is considering taking the following actions: ● 0₂ Install a new boiler that delivers the same amount of steam, but with only 2% excess ut and with an STR of 310°C. • Fix compressed air system leaks. The number of leaks that were detected was 10, and each of them has a 9-mm diameter ● Install a heat recovery unit that recovers 250 kW of energy which is used to replace the electric water heaters no Electric heaters used The capital cost of the project is SR 3,000,000. Calculate the following: a. Rate of thermal energy delivery to the steam by the old boiler. [2 points] b. Rate of natural gas consumption by the old boiler (in kg/s). [3 points] c. Cost of natural gas consumption (in Saudi Riyals) per year by the old boiler. [3 points] d. Cost of electricity consumption of the compressed air system and water heaters (in Saudi Riyals) per year. Assume the tariff is SR 0.18/kWh [4 points] e. Cost of natural gas consumption (in Saudi Riyals) per year by the new boiler. [4 points] f. Cost of electricity consumption of the compressed air system (in Saudi Riyals) per year after project implementation. [4 points] without heaters g. Annual financial savings (in Saudi Riyals). [4 points] h. The net present value (from the ESCO's point of view) based on an 8% discount rate. [3 points] i. Based on your answer in Part (h), should the ESCO agree to implement this project? [1 points] An industrial facility has an old boiler that consumes 20 MW with 8% excess ar, and the stack temperature rise (STR) is 360°C. The boiler consumes natural gas whose heating value is 54 MJ/kg. The cost of natural gas is SR 1.1/kg. The facility also has a compressed air system that provides air at a pressure of 8 bar and consumes 1,500 kW continuously throughout the year. The facility needs hot water and it is provided by electric water heaters that consume 250 kW continuously throughout the year. The facility owner would like to reduce energy consumption by hiring an ESCO on a 10-year shared savings contract, where the ESCO receives annual payments equal to 50% of the annual savings. The ESCO is considering taking the following actions: ● 0₂ Install a new boiler that delivers the same amount of steam, but with only 2% excess ut and with an STR of 310°C. • Fix compressed air system leaks. The number of leaks that were detected was 10, and each of them has a 9-mm diameter ● Install a heat recovery unit that recovers 250 kW of energy which is used to replace the electric water heaters no Electric heaters used The capital cost of the project is SR 3,000,000. Calculate the following: a. Rate of thermal energy delivery to the steam by the old boiler. [2 points] b. Rate of natural gas consumption by the old boiler (in kg/s). [3 points] c. Cost of natural gas consumption (in Saudi Riyals) per year by the old boiler. [3 points] d. Cost of electricity consumption of the compressed air system and water heaters (in Saudi Riyals) per year. Assume the tariff is SR 0.18/kWh [4 points] e. Cost of natural gas consumption (in Saudi Riyals) per year by the new boiler. [4 points] f. Cost of electricity consumption of the compressed air system (in Saudi Riyals) per year after project implementation. [4 points] without heaters g. Annual financial savings (in Saudi Riyals). [4 points] h. The net present value (from the ESCO's point of view) based on an 8% discount rate. [3 points] i. Based on your answer in Part (h), should the ESCO agree to implement this project? [1 points]

Answer rating: 100% (QA)

Here are the calculations a Rate of thermal energy delivery to the steam by the old boiler Thermal energy Power 1 Excess air 20 MW 1 8 20 MW 108 216 M... View the full answer