Solution

a.

An ‘empirical enquiry’ is a procedure involving measurement. There is a belief that science should progress by gathering as much data as possible. The data is then ordered until a pattern emerges which is the visible outline of an underlying physical principle or rule.

Quantitative data has a value on the numerical scale whilst qualitative data is descriptive and may involve interpretation. For example, ‘1 metre is equal to 39.37 inches’ is quantitative whilst ‘1 metre is longer then 1 yard’ is qualitative.

So what does this have to do with case study? A case study looks at one particular situation in some detail. The case is evaluated by acquiring actual data. In our application, it might be energy usage and cost over the year. Proposals are presented and evaluated, again in a measurable way. You cannot use statements such as ‘This is a more costly solution but is balanced by a reduction in environmental damage.’ You have to provide a measure of you cost environmental damage first.

The case study therefore should have focus on a closed system that can be analysed in depth, and the analysis should involve the comparison of quantitative data.

Qualitative research is the process of collecting, analysing, and interpreting non-numerical data, such as language. Qualitative research can be used to understand how an individual subjectively perceives and gives meaning to their social reality. Qualitative data is defined as non-numerical data, such as text, video, photographs or audio recordings. This type of data can be collected using diary accounts or in-depth interviews, and analysed using grounded theory or thematic analysis.

Quantitative research involves the process of objectively collecting and analysing numerical data to describe, predict, or control variables of interest. The goals of quantitative research are to test causal relationships between variables, make predictions, and generalize results to wider populations.

b.

Generalisation is the idea that you can discover a general principle by the investigation of a single case. This is sometimes but not always true. If the case is unique then it is unlikely to reveal more than the very specific facets of that combination of entities and circumstances. It is best to design a case study so that the findings can be of greater value because they can be applied to related situations as well. Case studies that lend themselves to generalisation will tend to require more data to be collected and involve a greater depth of analysis. This is because you try to remove the restrictions that limit the scope (but simplify data collection) by modifying the scenario.

For example, a case study that tries to measure the output from a wind turbine at low level will be influenced by physical obstructions, but to consider a variety of heights high above building level make the results more generally applicable in that region.

Solution

a.

Be careful about your own expectations for the case study. You may be quite experienced and have a good intuitive idea of what to expect, but it is important not to prejudice the case studies by directing your data collection and analysis towards what you believe the outcome should be. Be open minded and critical. Look for flaws in what you may have accepted up to now as obvious and correct. It is normal to want the introduction of a renewable energy technology to make economic sense, and this may even be the motivation for the case study. But you must conduct the case study in a completely objective balanced way and report truthfully if the proposal is economically unsound. Don’t ignore factors such as maintenance of equipment, running casts, repairs etc that are important ongoing costs to swing the argument.

b.

Renewable energy is normally installed in public buildings, and you could look at these. One example is shown below.

Back in the early nineteenth century, the subsistence economy of Lewis was based on a plethora of small vertical axis or 'Norse' waterwheels. These powered the grindstones that ground the barley and oatmeal which formed the staple diet of the locals - wheat was unsuited to the infertile, acid soils and cool, damp climate of the Hebridean islands, and potatoes had not yet arrived. Change was just round the corner. Britain's Industrial Revolution was taking off, agricultural production on the mainland had taken great strides, and local landowners were keen to modernise.

In those days, the Mackenzie's built three modern horizontal axis watermills on the island in the years up to 1816. One of the new watermills was actually in the grounds of Seaforth Lodge itself, the home of the Mackenzie's. The site was known as Willowglen, the water came from the River Glen. What was initially dubbed the Stornoway Mill later became known as Latta's Mill after the death of John Latta in an accident there in 1834 — or possibly because the Latta family operated the mill for more than 20 years.

Figure 5: Original technical drawing of the design for the Stornoway Waterwheel. [Source] used under fair dealing.

Solution

a.

The soil temperature near the surface can be estimated from the average air temperature over the year, but the situation is complicated by the nature of the soil, whether there is water present and the actual depth. The information about how the temperature varies with depth is generally known, but the specific temperature depends very much on the nature of the rock. Drilling bore holes is expensive (over £5,000 for a single hole, but becoming cheaper as more are drilled).

The best approach is to gain information from existing operational systems. Find out who has installed ground source heat pumps, what the configuration is and what energy is being obtained. By collating the data from multiple sites in an area with similar geology, it is possible to develop working guidelines for heat pump installation in that region.

There are different types of ground source heat pumps, and it is important to evaluate which system is most suitable for your home. The type of system and the scope of the installation project will also determine the overall costs of your ground source heat pump.

The costs associated with a borehole heat pump installation are directly proportional to such factors as borehole depth, borehole casing and sealing materials dimensions. In order to make sure that you will make the most out of the ground source heat pump boreholes you are planning to drill, you can order a geotechnical survey to be carried out beforehand.

Solution

a.

The argument will of course be your own, but an example is shown below:

Energy Storage Methods for Domestic Renewable Energy

This case study will compare the cost effectiveness of four different methods of storing energy to try to balance the intermittency of a 2.5 kW wind turbine. A storage time of up to one week is required of the storage mechanism. The options are a bank of Li-ion batteries, Lead-acid batteries, a hydrogen storage mechanism and the use of a large thermal mass. The cost and maintenance of all ancillary equipment and electronic components will be considered. The procedure will be to determine the capacity of each system. From this a list of components will be generated. Each system will be costed (including installation), and an evaluation will be made based on efficiency, cost, convenience, safety and space.

b.

Assuming the above proposal is approved (and this is not certain because the scope might be too great), an outline report might look like this:

c.

Direct quotations, statements that need to be substantiated or backed up, sources of data, information about devices and equipment, web sites explaining how things are connected, all need to be referenced. It is possible to refer to a textbook that describes all the basis information to avoid having to reference everything or define every new term.

Harvard referencing will be used.