STEP Solar Thermal Electric Panel
Discussion
Not only is the STEP hybrid system effective in its aesthetics but it is also more efficient than its two standalone counterparts. The estimated overall efficiency of the STEP system is estimated to be 50% while a separate thermal and separate electric system is estimated to be 26% for the same roof area. An assumption for the thermal systems is that they are of similar makeup and their efficiency is based on an ambient input temperature.
If this setup was placed on an average home, of 2400 square feet, the roof area of an average sloped house would facilitate the placement of twelve times the surface area tested. If the data was extrapolated from the four hour test period to an average whole day production the following results would apply. For an average yearly household consumption of 10.7 MWh a year, four times the collector area tested would be needed. Note that the hot water would be used for space heating as well as for domestic use. This does not mean that all of the hot water and energy needs would be met for a particular season because this is based on average numbers. The average cost of electricity is about ten cents a kWh. This would essentially save the owner $1070 a year in energy costs. The proposed system would cost about $28,000 as specified in this report; this system does not include inverters or batteries, which would add another $8,000 to the system cost, for a fully sustainable system. The payback would be twenty-six years where the rated life of the solar panels is twenty-five years. This is also assuming that the price of electricity is stable. The cost of energy is always increasing and the payback would be shorter as prices soar.
This test went a long way in addressing the viability of solar energy collection systems. While there is an initial investment a payback is possible especially as energy prices continue to increase. A major goal of this system was to use building integration strategies to make solar more aesthetically pleasing to the average consumer. The global impact of solar systems is seen through their lack of pollution. Although the components do require a certain amount of pollution to manufacture, the operation of the systems do not. For developing countries or the less fortunate, the solar thermal system proposed here can be drastically reduced in cost. The system we used had copper as its building material; cheaper metals would reduce the cost.
With a properly sized and installed system this technology can be used today for sustainable housing. Along with water collection/restoration systems and waste management systems the home would be completely independent. This same technology can be used in the commercial sector as well. Just like designing for different climates, the systems would have to be tailored to fit the particular needs of the business.
Overall the experiment was a success. The only major problem that was not solved was the fluid flow rate could not be manipulated. It was deemed to not be a major factor because without a constant inlet temperature the performance would be very difficult to track. The tests were done by the two students attached. We did however receive some help developing the relay board was utilized from John Tyler, who is a resident engineer at UMR. The experiment was held up on several occasions due to bugs in the systems and therefore wasn’t done in January. Two major things that we would have changed would be a variable speed pump with a separate tank to have a constant inlet temperature and a load that would work all the panels as a single unit.