|Fig. 1: The Clemson University solar-powered mobile health clinic. (Sourtesy of Clemson University)|
In the United States and around the world, disparities in health outcomes have always existed between social class, race, gender, and even age.  It has been noted that even having access to health insurance does not necessarily equate to having full access to treatment, since some residential areas may be too far from clinics or hospitals. As such, mobile health clinics (MHCs), are particularly useful because they can help serve the full spectrum of at risk populations. After all, if people cannot afford to go to hospitals or clinics, MHCs can come to them. In the US, MHCs have provided millions of Americans with access to healthcare when they might not have been able to obtain it otherwise.  Given all that MHCs have done for equal opportunity healthcare in the US, its potential to do good for developing nations, where equal access to good healthcare is even more important and more difficult to achieve given factors such as poor access to safe water supply, sanitation facilities, and overcrowding. 
However, when considering the efficacy of MHCs in more removed areas, especially those in developing nations, it is important to consider how to ensure that mHealth units have a consistent energy and fuel supply. After all, MHCs breaking down in the middle of a deserted farm road is of no use. To approach this problem, one solution that has been offered is that of a solar-powered mobile health unit (Fig. 1).
|Fig. 2: Comparison of cost per kWh between solar power and traditional fuel, assumng a price for the latter of $1.20 per liter.  (Source: S. Xiao.)|
Clemson University created an MHC that draws 100 percent of its power from a special solar battery system. This not only eliminates the noise and fumes of a traditional generator, it also decreases operation and maintenance costs.  This system is optimal because MHCs are required to sit in remote locations for eight or more hours a day. Being able to utilize solar power is hugely beneficial for the efficiency of this system.
Fig. 2 compares the costs of using fuel and solar energy to power a system using average fuel costs in Africa. This comparison is appropriate because the areas that would benefit most from solar-powered MHCs are developing nations that lack power grids and consistent fuel sources across the country. As the graph shows, the price per kWh of using solar power is merely a fraction of what the price per kWh of using traditional fuel is.
Ultimately, analysis of the cost of solar power as compared to traditional fuel shows that having a 100 percent solar-powered MHC is the most energy-efficient method of action. In addition, when it comes to places that do not have consistent access to power grids or fuel supplies, solar power makes MHCs even more portable than previous ones. MHCs are one of the most promising developments in healthcare, largely because they make it truly accessible to all at-need populations. Making MHCs more energy efficient just means that they can further their reach and benefit even more people around the world.
© Sophia Xiao. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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 A. Prabhakaran et al., "Cost of Ambulatory Care by Mobile Health Clinic Run by a Medical College in India for the Year 2008-09," Indian J. Public Health 58, 100 (2014).
 L. Osby, "Clemson's Mobile Health Clinic Powered By the Sun," Greenville News, 10 Oct 17.
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