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)
Follow the numbered steps below to run a HOMER® analysis.
Location and Time Zone - Use the map to indicate your approximate location [more info]
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.
Power Assumptions - Override the default values for the cost and availability
of the electric grid, any on-site power generation with local values if known.
[more info]
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.
Financial Assumptions - Enter the Real Interest rate [more info]
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.
Electric Load Inputs - Enter the type and number of electrical devices used in the health clinic and the time of day they are used. [more info]
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.
