Qualitative And Quantitative Examination Of Solar Home System
Introduction to the problem
Four out of five people on this planet simply turn a switch. The lights come on, a computer powers up, hot water flows from a tap or machines start humming. One out of five, however, does not have a switch to turn, since he or she simply has no access to modern energy with detrimental impact on the livelihood and well-being. There are various reasons why 1 billion people are still without electricity and 3 billion rely on open fires and traditional stoves for cooking. Operating electricity grids in remote areas is not economically viable for many electricity suppliers in developing and emerging countries and markets for off grid technologies are not yet developed. Initiatives for promoting modern cookstoves, in turn, face numerous social, cultural and economic challenges.
The energy crisis is the concern that global demands on the limited natural resources used to boost industrial society are diminishing as demand increases. The energy crisis is a massive and complicated argument. The energy crisis is a phenomenon that is running and going from bad to worse there are natural resources that are used by people and they are limited. Although they occur naturally, it can take hundreds of thousands of years to replenish stores. Governments and interested people are working to make the use of renewable resources a priority, and to decrease the irresponsible use of natural supplies through greater conservation.
Domestic or solar home systems (SHS) are independent photovoltaic systems that offer a cost-effective way to provide electrical power for lighting and appliances to remote homes without a wired or grid connection. Solar home systems provide power to many thousands of homes in remote locations in the world. In rural areas which are not connected to the grid, SHS can be used to meet the energy demand of a house that has basic electrical needs.
SHS are the technology that is used to power electricity to run household appliances like bulbs, or other light sources that use considerably lower amount of power. These light sources are measured using light sensor to obtain their illumination. The statistical tests are done on their illumination to find the reliability of these data.
Methods and materials
SHS normally function at a voltage of 12 V DC current and provide power for low power DC appliances such as lights, radios and small TVs for about three to five hours a day. Moreover, these systems make use of devices like cables, switches, plugs, and structural parts and power conditioners or inverters. These devices change 12/ 24 V power to 240VAC power for larger appliances. Kit 2 was used to produce the light as was instructed in the power point slides
- Rechargeable lithium battery 3. 7V 3000mAh,
- Polycrystalline silicon solar panel 5V 4W,
- 3 X 1W LED bulb
- 3, 5, 7- meter cable and fitting for LED,
- Solar mobile phone charge.
Kit 3 which was Amprobe LM-100 light meter was used to take readings of luminosity from the light sources.
The data obtained needed to be done analysis on these datasets. The luminosity was calculated at different places. There are three scenarios floor, desk and reading. In each case, there are 9 positions. Position 9 is supposed to be the nearest to the light source.
Results and discussions
Different statistical analysis has been carried out with the given data. Firstly, the trendlines of group data were made at three different states which are floor, desk and reading. There are readings for 9 locations in each of the states. Similarities are there between the groups results. The location number five has a slight peak in the results as can be observed. This might be because the bulb’s position is perpendicular to that certain location. This causes the meter to have slight high lux. For the floor readings in the 1W bulb, the groups got data readings. Group 5 had slightly lower reading than the rest groups comparatively. This can be due to few reasons. As has been indicated before, groups were instructed to use kit 3 to take readings for the testing. For some circumstances it might be that their kit had a fault and thus discrepancy occurred. On the other hand, it can be observed that group 5 had their results higher than other groups at all positions and they were significantly high. This might be because they were using a different or maybe different kit. With the increase in wattage this discrepancy can be seen to reduce. At 1W, the group average reading was approximately 5 lux and the group 5 had higher average of approximately 9 lux.
Standard deviation
It can be said that the 3 watts had comparatively higher values. This chart includes the median values. The bars have a line in the middle that shows the median values of luminosity. The smaller the box is the smaller the standard deviation is that means that the groups’ results are precise like in locations 3, 4 most times and vice versa. it can be observed the 2W bulb reading had the greatest number of precise data. The 3W bulb had larger illumination and normally a higher standard deviation. This might be because the 3W bulb had higher potential to emit light. Also, this had a bigger spread of readings. Trendlines are consistent for the 1W data whilst quite inconsistent for the 3W data. Also, the trendlines are quite stable from the locations 6 onwards. The standard deviation in location 2 is small in all 3 cases. Theoretically at 9, the illumination should be highest since its placed directly below the source. But since this is not the case, there might be inaccuracies.
Similarly, on the desk data, a similar trend is observed. This time the trend is more stable but there is a larger deviation for all the data. The source is 1. 2 m from target so there are higher illumination readings. This had a compact set of data. The different powered bulbs had a lesser difference in illumination compared to floor data. On the other hand, the reading data had a different trend. For the reading data, the trend is very unstable. Also, the deviation is not consistent. There are some locations where the deviation is very high, and some locations have very low deviations. Since target is very close to source, the illumination is highest for all. Discussion There are different uses of light in the world. There are different light levels required for carrying out different tasks. The minimum is about 20-50 lux for public places according to the PowerPoint slides. Most of the data don't produce enough lumens to reach the minimum illumination. In the floor data only, group 5 fulfills this. Group 7 has enough data of illumination that might be helpful for short-term work activities of the data from reading tasks might be feasible for activities carried out in home & warehouses as per lux levels.
It can be said that there are errors in the data recording. Few of the reasons are human errors, fluctuation of power, accumulation dust on meter, aging of the bulb. Since the experiment is being carried out in the kitchen, there are reflective objects like cooking utensils and other materials. To achieve good and accurate measurements, certain measures and precautions need to be taken. The measuring devices need to be properly calibrated in order to achieve correct readings. High range kit to measure, the kit needs to be of higher range than kit 3(Ampro). This can be higher than 100 LM. Suggestion can be of a range of 120-150 LMs. Moreover, the optical and electrical parameters need to be considered to get rid of any inaccuracies. like physical quantities and standards, such as the luminous flux, luminous intensity, distribution of luminous intensity and color within the radiation pattern, efficacy and efficiency should be considered Since dark objects absorb light so light objects need to be avoided should be done in a dark room with no reflective objects. Also, the optical and electrical parameters need to be considered to get rid of any inaccuracies. Sensor need to be cleaned regularly.
Conclusion
Solar Home Systems helps many societies that live in distant rural areas by providing financial support in their day to day life. Wired power supplies are not always so much reliable and in developing world, changes in voltages can damage the devices. Solar Home Systems are more specifically reliable with LED lights even though they need storage support they are profitable. This could help boost the economy of developing nations. It is a durable and portable system and has more value in remote rural areas of developing countries such as Africa and Asia to meet energy demands.
