Diesel to be used as back-up fuel for Natural Gas Plant

Feb 15, 2023 News

---

…geo-technical studies, onsite surveys still to be done – Project Summary

Kaieteur News – The Guyana Government is pursuing the construction of a Natural Gas fired electricity generation plant, capable of producing some 300 Megawatts (MW) of electricity to be supplied to the national grid.

Touted as a means to transition away from traditional fossil fuels, such as Heavy Fuel Oil (HFO) to a renewable energy mix, the Natural Gas Fired Plant is among the flagship projects earmarked for West Demerara.

According to the most recent Project Summary for the Gas to Power Project submitted by the Guyana Power and Light Inc., (GPL) the intention is to install generating capacity of 300MW of Combined Cycle Gas Turbine (CCGT) and that the CCGTs will be capable of combusting rich and lean natural gas as their primary fuel.

It should be noted that GPL is not the developer of the project, which was recently highlighted by international Attorney-at-Law, Melinda Janki.

The primary fuel, GPL said, will be supplied by an onsite Natural Gas Liquefaction (NGL) facility. That NGL facility will be supplied with pipeline quality natural gas via a 12-inch diameter pipeline, connecting to the Floating Production Storage and Offloading (FPSO) vessels located in the Atlantic Ocean. “Additionally, the current functional technical specifications of the 300MW GTPP require the CCGTs to consume propane and/or diesel as their back-up fuel. The definitive back-up fuel for the CCGTs will be known at the end of the Engineering Procurement and Construction (EPC) bidding process.”

According to GPL, the power plant will be designed for the full operating range while for natural gas, diesel fuel oil and propane firing, while maintaining emission requirements and that the plant will be designed for sustained “simple cycle” operation to accommodate conditions where the steam turbine(s) are unavailable due to a forced outage or scheduled maintenance.

As it relates to the use of diesel fuel, GPL said its supply system will consist of some key components, including, a Diesel Fuel Oil Storage Tank(s) with a minimum aggregate capacity equivalent to three days of fuel for the maximum continuous rating of the power plant.

The planned minimum storage capacity for three days of fuel is expected to be 22,364 UK barrels, which is equivalent to 1,073,471 imperial gallons.

Additionally, there will be the need for Fuel Oil Unloading Pumps, Diesel Fuel Oil Forwarding Pumps, one for each Combustion Turbine Generator (CTG) and Control Valves, one for each CTG, fuel oil recirculation system.

According to GPL, the diesel fuel oil system will be a permanent system. Additionally, the plant will require emergency/Black-Start Diesel Generator Day Tank sized to accommodate the black- start of the power plant supplied with Diesel Generator.

As it relates to the second option for backup fuel, GPL said Propane will be supplied onsite by the NGL facility and stored onsite in ISO tanks and that the storage capacity would be for four days to support continuous plant operation at full capacity.

According to GPL, the estimated capital investment for the development of both power generation and inclusive of water supply and treatment, is currently pegged at US$300,000,000 and is subject to review based on tenders’ submission

NO STUDIES

Poignantly, the document submitted to the Environmental Protection Agency (EPA), at the end of January last, noted that at this time “no geotechnical study or onsite surveys have been done for the project site” namely the Wales Development Zone.”

GPL said, “…upon the completion of the geotechnical study, the results will be provided, along with other relevant studies.”

The earmarked plot of land that is required for the 300 MW Natural Gas-fired Power Plant, is approximately 100 acres and this, according to the project document includes the substation and other critical power evacuation facilities.

It was noted however, “at the time of project execution, the required project footprint may vary, but not in such a manner that the project would exceed the available space described.”

Providing some details on the project, GPL said, the Power Generation project shall consist of a combined cycle configuration as recommended by the EPC Contractor and accepted by the Employer, consisting of multiple Gas Turbines (GTs) exhausting into Heat Recovery Steam Generators (HRSGs).

It said, the steam produced from the HRSGs will power one or more Steam Turbine Generator(s) (STGs).

The STG exhaust steam will be condensed in a water-cooled condenser, which uses a circulating water system and cooling tower to displace steam cycle heat.

---

• Diesel, Government, Guyana, Heavy Fuel Oil (HFO), Natural Gas

---