SAMPLE POSTER

Introduction

In our project we test 3 different devices for boiling water and then comment on their cost efficiency based on their power input (P) and the time (t) needed to boil 100 grams of water. These three devices are: a boiler, a hot plate and a regular microwave oven. Each of these electric devices requires a different power input. The process of temperature monitoring was conducted with a digital thermometer of high precision, while the process of time measuring was conducted using a digital stopwatch. Based on the above, we were able to identify the exact time needed for the standard quantity of water to reach 100° in the 3 aforementioned electric heating devices. Throughout the experiment we made sure, prior to taking time measurements, that the initial temperature of the water was 25°. This way, the change in temperature (ΔΤ) for water was the same in each case. This procedure was carried out 6 times for each device. Finally, since we are aware of the power input, temperature change, time of heating and mass of water, we are able to determine the energy consumed and, hence, the total cost of the heating.

Raw Data

Device Power Input (W) Time taken (s)

Boiler 2200 55

Hot Plate 450 390

Microwave Oven

1200 84

Research Question

Which is the most cost-effective way to boil water?

Processed Data

BoilerHot Plate

Microwave Oven

0

50

100

150

200

250

300

350

400

Total Cost (E-4 €)

Time taken (s)

Energy (E+3 J)

Total Cost (E-4 €)

ConclusionThe boiler’s high power input justifies the fact that it is this device which boils water faster. However, from an economic perspective, the microwave oven is the most cost-effective device. The reason this is that this device takes only slightly more time to boil water than the boiler, but still spends less energy. This could be explained by the fact that the microwave oven has a lower power input.. Moreover, the data shows that the hot plate requires more time to boil water and is the most expensive device to use. To sum up, microwave ovens win the day!

Limitations

• We have to assume that the power supply is constant.•We assumed that the hot plate experiment was a closed system and, therefore, there was no thermal energy transfer between the transience and the hot plate.•In this laboratory investigation we do not take into consideration the initial investment needed to buy each of these devices when commenting on the final cost.•Electric equipment wears off as time goes by. This means that the devices’ efficiency gradually decreases. As a team we were not aware of the time period the devices were purchased or manufactured. This factor may have negatively influenced the accuracy of our results and the validity of our comments.

where 0,08761 is the cost in € per kWh