A hospital located in Tanzania is connected to the country’s electrical power grid but experiences power outages often and for a very variable length of time. The hospital must have a reliable and continuous power supply in order to function effectively and for patient safety. A system is to be developed to enable power to be available for the use of the hospital during power outages in the grid supply.
Tanzania has a grid supply of frequency 50Hz, 380V ph-ph or 220V single phase. It is known that the hospital has an average load to the grid of 100kVA and a peak load of 135kVA. More detail than that is not known at this stage, so the specification that follows is based on assumptions that may not be correct for this particular site.
A power supply is to be available to the hospital at all times.
The peak total load demand of 135kVA is to be supplied by a diesel generator. It is intended that this generator is not to be left running during periods of normal supply but will be started when the supply fails.
A backup diesel generator of 50kVA is to be available for use in critical areas should the main generator fail to operate when required.
A high integrity, uninterruptable supply of average 4kVA and peak of 12kVA is required for the three operating theatres and a separate high integrity, uninterruptable supply of average 3.5kVA and peak 4.5kVA is required for the computer centre.
The switching over of the sources of the supplies to the operating theatres should be uninterrupted and should not involve voltage spikes of greater that 10% of supply voltage. The supply to the computer centre should be virtually free of spikes.
A separate battery supply is to be made available for emergency HF SSB communications transceiver with a maximum transmit power output of 100W and should be rated to provide an average power of 30W for 2 weeks.
A UK charity has negotiated a loan from a UK bank for the purchase of the capital equipment for the project at a fixed annual discount rate of 4.8% to be repaid monthly over 20 years. Equipment can be sourced from any country but all transactions should be made in £GB.
Your task is to specify and source the equipment required for the project and to present an outline of the system in the form of a block diagram and a clear list of the equipment to be used as well as sufficient information to allow the equipment to be purchased from a supplier. As a minimum, this should include, but not be limited to, all those parts shown in bold above. You should cost the equipment and calculate the total capital cost of it and the monthly repayments that will need to be made by the hospital to the bank.
find the suitable equipment and cost it.