This online software tool uses HOMER Energy's HOMER® optimization model to assist health care providers design appropriate power systems for their rural health clinics using combinations of diesel generators, utility power grids, batteries and photovoltaic arrays. Additional information: "Powering Health: Electrification Options for Rural Health Centers" (PDF 660 KB)
The amount of energy available from the sun is directly related to location. HOMER obtains monthly average solar resource values from a variety of databases at NREL and NASA. These are calculated based on the latitude and longitude of a site and satellite measurements of annual cloud cover.
In areas where the electricity grid is available only part of the day, the scheduling of the grid can have a significant impact on the design of a suitable power supply system.
The availability and cost of supply and installation of PV panels, batteries and diesel fuel will vary by location. The default values entered here are roughly accurate for much of Africa, but should not be relied upon without verification. When calculating the cost of PV, include the cost of all related components (the cost of the panels, installation, mounting frames and other hardware), but not the inverter, which is sized separately by HOMER.
HOMER minimizes the discounted Cashflow of the project, The interest rate determines the tradeoff between the initial capital cost and future operating costs. It has a significant effect on the optimal system design. Lower interest rates will favor PV over diesel generators. The Real Interest rate can be approximated as the difference between a bank's interest rate on loans and the estimated rate of inflation.
The table is populated with common equipment types found in rural health clinics including typical power ratings. The time of day that power is needed and the peak power demand have an impact on the sizing of equipment and the optimal configuration. For the most accurate simulation, this step may require a walk-through of an existing clinic. If there is no clinic yet, refer to the link provided above for guidance on estimating the potential electrical load.
Once you have defined all the necessary inputs HOMER will analyze every possible combination of power supply options that meet the demand. The results are ranked low to high based on the cost per unit of electricity over the project lifetime.