The major difference from our prototype 3 and prototype 4 is that prototype 3 is powered by a power striper which costs money to power the electricity. But our prototype 4 is powered by a solar panel to get an average of 75 ml of fresh water while prototype 3 produced an average of 96 ml of fresh water over a period of 6 hours. Although prototype 4 got 21 ml of less water than prototype 3, it is a much more cost efficient and eco-friendly way of getting fresh water.

To dive more in depth on why we chose prototype 4 over prototype 3, we need to learn about the workings of solar power. Solar panels installed, normally on a house or building, capture the sun's energy to create DC electricity, or a direct current. Directing currents flow in a wire in ONE direction. Normally, an inverter in people's homes will convert the direct current to an alternating current (can flow in two directions) which is normally used in homes and businesses. In houses and business, excess electricity can go back to the grid to be reused again, which saves power!

In terms of our device: (electricity bill not counted)

Electric: Solar:

Power Strip-$12.69 Small Solar Panel (used in our device)-$9.99

Batteries (if needed)-$6.49 No batteries needed at all

Fountain Pump-$11.99 Fountain Pump-11.99

Total: $30.17 ($24.68 w/out battery). Total: $21.98

As you can see, our solar powered model costs $21.98 to pay for our powered components while our electric models costed $24.68 to pay for the electric parts we needed for our model. This is cheaper for our device to combat drought, which is designed for affordability and has a budget of $40, which shows that our fourth prototype is cheaper than our third prototype. This is reflective of real world where you have to pay an enormous electricity bill whereas you can use less electricity through solar power. In fact, the IEA has declared that solar power is the cheapest source of electricity right now.

Simon Evans. Oct 27, 2021. Solar Is now Cheapest Electricity in history, confirms IEA. URL- https://www.resilience.org/stories/2021-10-27/solar-is-now-cheapest-electricity-in-history-confirms-iea-2/

Solar panel has many more benefits than its electric counterpart, which led us to use solar panel for prototype 4. One major advantage is that you can leave the solar panel outside, even in the middle of heavy rain. If electric parts were to be exposed, this would cause serious damage to the electric parts assuming they are presumably exposed. It's a good thing that we ran our electric models when it wasn't raining! Another advantage is its carbon footprint. Solar power produces a very limited, if not nonexistent carbon footprint while electricity, powered by non-renewable (will run out, limited) fossil fuels produce a large carbon footprint, which pollutes our cities and harms our animals. What is the drawback for this splendid efficiency? Not all sunlight is reflected on the solar panel. About 15% of sunlight is reflected and used on most modern-day solar panels. However, scientists are developing a new solution for solar panels to reflect most of the sunlight applied. Even as of now, the efficiency advantages of solar power far outweigh the flaw of producing limited energy, which will anyways be fixed in a few years!