ABOUT GAS GENERATORS: FREQUENTLY ASKED QUESTIONS
- FINANCIAL CONSIDERATIONS
How is a gas gen-set convenient for standby, compared to a Diesel?
A simple Total Cost of Ownership analysis can show that looking at the life of a standby gen-set, considering all costs associated with a Diesel generator, (such as fuel maintenance, the first fill of diesel and the difference in cost between Diesel and Natural Gas) the total cost of the standby asset for an end user favors Gas vs. Diesel even in a standby application.
What is the difference in cost of fuel expense between Diesel and Gas Gen-sets of the same size?
This depends on regional variations by countries. In most of Europe, at current prices, running a gas generator would cost in fuel about 1/3 per hour than running an equivalent diesel at the same load.
What is the cost of self-produced electricity from gas?
Compared to electricity prices from the utility, there can be high-tariff times of the day or the year where the cost of kWh self-produced from gas is lower than the kWh purchased, therefore there can be a positive revenue stream.
- GAS RELIABILITY AND EMISSIONS
In case of power outage, would gas also stop flowing?
No, this is not the case. Gas infrastructure is independent of grid power and often self-powered. Compressor stations are self-powered using approximately the 3% of natural gas produced. Natural gas distribution systems operate at a reliability rate exceeding 99.999%.
What emissions levels does a Natural Gas generator meet?
Typical Natural gas generators already emit much lower emissions than traditional diesels. Emissions of our Gas Gen-Sets, when equipped with a catalyst, can be compared to those of Stage-V Diesels, but without particulate.
Does a standby generator need to meet emission regulations?
Generally, standby generator systems are exempted from emission regulations. However, at local level there might be restrictions on particulate and other pollutants that would restrict the use of diesel, but do not represent an issue for gas. At European level, there is a trend of new emissions limits in the major cities (such as Madrid recently), also on standby assets.
What is the difference to install a gas generator and a diesel generator?
Pramac gas gen-sets are very similar to equivalent diesel ones, and the requirements for installation (civil works and electrical works) are basically identical. The difference would be related to plumbing, because with gas generators a gas plumbing company needs to provide the gas feed line from the main distribution point of the site to the gen-set. Of course, gas generators do not require on-site fuel storage system, therefore tanks or fuel transfer pumps are not needed.
What is the autonomy of a gas generator (run-time)?
Unlimited, with a continuous supply from the natural gas pipeline.
Gas generators are slow to start and respond poorly to load insertion. How Pramac generators are different?
Our gas generators feature unique proprietary system for quick start and “rich burn” optimized combustion technology that allows them to perform similar to equivalent Diesel. Pramac gen-sets are optimized to meet the requirements of NFPA110 10 and ISO8528-12 for standby systems. Typically, starting time is less than 10s and first load step greater than 50%.
How does the generator connect to the gas line?
There is a gas inlet port on the side of the generator. Depending on the model, this is either threaded or flanged. Contractor shall bring the gas pipe to the generator and provide necessary pressure reducer to match the required low pressure feed.
What pressure does the gas need to be delivered at?
Pramac gas generators are optimized to run at ultra-low pressure. Depending on the model, this can be as low as 17mbar (1.7kPa) and still allow the gen-set to run at full power. Regulations and permitting requirements tend to be more strict for pressure above 50mbar, but with our gen-set this is not an issue as they run on low pressure.