Generator Fuel Tanks
Generators produce electricity during power outages. This electricity generation is achieved by converting the mechanical energy generated by the combustion of fuel into electrical energy. For more detailed information, if there is no fuel in the generator during the power failure, the generator cannot perform its function in case it is needed. Fuel storage should therefore be carried out to prevent such a possibility. The fuel is stored in a specially designed fuel tank. Various considerations must be taken into account when selecting and installing a suitable fuel tank.
Fuel Tank Capacity Determination
When determining the capacity of your fuel tank, you must first determine how much fuel you need. You can calculate the minimum storage capacity by estimating the following three parameters:
(1) Urgent Stock: How much fuel is needed in case of over-consumption and delays after power outage?
(2) Supply Time: How long is the fuel supply time from the seller to the location of the generator?
(3) Supply Time Storage: What is the amount of fuel to run the generator until the fuel is supplied from the seller?
Depending on the above three parameters, the minimum amount of storage is determined as adjacent:
Minimum storage capacity = Urgent Stock + Supply Time Storage
What is the optimum fuel storage capacity?
In the case of short-term power outages, a smaller storage tank will be sufficient for the fuel requirement. However, because the tank is small, you need to buy much more frequent and small amounts of fuel. The smaller the tank, the lower your cost when purchasing the generator; however, the amount of fuel consumed per unit is higher. Large storage tanks are used in large commercial establishments or in areas where power outages are frequent and long. In this case, you can buy fuel in less and larger batches. However, the cost of purchasing the generator is high. At the same time, maintenance costs will be high in the long term. On the other hand, the amount of fuel consumed per unit is reduced because you order large quantities of fuel to be delivered at one time. However, you should also calculate the hidden costs that may arise from hazards arising from a larger amount of fuel storage
Types of Fuel Tanks
Generator fuel tanks are usually of three types:
- Bottom base tanks
- Underground storage tanks
- Aboveground storage tanks
Bottom Base Tanks
If you store less than 1,000 gallons of fuel, you can use the base of the generator as a fuel tank. As the name implies, the bottom base tanks are fixed to the base surface of the generator set. Bottom base tanks are rectangular and double wall tanks. This increases the tank’s resistance to any leakage. Both tanks were built using heavy steel welding. Tank filling system; The inlet valve should be designed to close automatically when the tank is 95% full. After loading, the primary tank is tested at 5 psig and the secondary tank at 3 psig
Underground Storage Tanks
If you need to store more than 1,000 gallons of fuel, you can choose underground storage tanks or above ground storage tanks. Underground storage tanks are more costly, because in order to build a longer lifetime, they must be protected from environmental effects. Underground storage tanks can be constructed from glass fiber reinforced plastic. Such tanks are often highly fluted to ensure structural rigidity. Alternatively, underground storage tanks can be manufactured from steel but with appropriate cathodic protection against corrosion from the ground water. Likewise, the pipe from the underground storage tank for the generator may be glass fiber reinforced plastic or cathodic protected steel.
Leakage and debris in underground storage tank systems can be expensive and difficult to correct. Such systems should be equipped with overflow and spill prevention equipment and procedures. In the worst case scenario, the installation of underground storage tanks should be so as to contain a limited area of fuel spillage or leakage. Therefore, the underground area is surrounded by concrete floors and walls. After the underground storage tanks are loaded in a specific area, the outer region is filled with sand and gravel.
Aboveground Storage Tanks
As the name implies, these tanks are mounted on the ground floor. The structural features of these tanks are similar to those of underground tanks, but the installation procedures vary widely. The reason for this is the different factors that should be considered to minimize the dangers. Aboveground tanks have a fire hazard which may spread to other facilities in the surrounding area. For this reason, these tanks must be at a distance that will not affect such facilities. Trenches should be built around the tank for leaks that may occur. The volume of trenches should generally be up to 110% of the tank volume. Surface storage tanks must be protected from weather conditions with appropriate protective structures.
Approvals and Standards
Approvals of tanks with low capacities may be exempt. Product information and forms should be supplied near the tank, such as manufacturing drawings, pipe design, and manufacturer’s installation instructions.
Various standards must be followed during the manufacturing and assembly of generator fuel tanks. NFPA related sections for generator fuel tanks are NFPA30 and NFPA37.