A Short Questionnaire

 

BACKGROUND QUESTIONS

We need as much background information about your project as possible, so that we can advise you on legal, financial, engineering and environmental matters. The enormous variety of schemes and the budgets means that there is seldom only one possible solution.

1. Are you enquiring as an individual domestic user, a consultant or a company engaged in equipment sales?

2. Are you a site owner who is investigating a specific project, and are there any disputes or potential disputes with your neighbours?

3. Are you looking for information, design and/or a quotation for suitable equipment or a “turnkey” project?

4. What is your rough time scale for this project, bearing in mind that most civil works can only be carried out in summer?

5. What is your budget per kW of capacity or what do you expect to spend in relation to the annual return? (price/earnings ratio)

6. Are there any specific environmental considerations relating to migratory fish, conservation or areas of special scientific interest?

7. Would you describe yourself as ‘hands on’ ‘keen to learn’ or ‘hands off’?

ABOUT YOUR SITE

• Sites fall into three general categories. Those with storage ponds, those with leats and those situated on a weir.

• Small streams can be measured by the time it takes to fill a calibrated container or with a calibrated weir.

• Medium streams with flows greater than 10 litres per second can be measured using a measuring weir in the form of an opening of an appropriate size to carry all the water. The water quantity is then read off from a weir table.

• Larger rivers can be measured where the cross section of the river is fairly regular. A taut wire or bridge is used as a reference and the depth and velocity are then measured at regular intervals across the river so that the cross-section and average velocity can be calculated. A current-meter or float can be used to measure velocity with a correction factor of 0.6 for a rocky stream, 0.75 for an earth channel or slow river and 0.8 for a rectangular smooth channel.

INFORMATION REQUESTED

1. The name of the river or stream identifying your site with a map reference, post code or satellite image
2. A general site description including features such as waterfalls, weirs or sluices is often helpful.
3. A large scale map, preferably with contour lines should be supplied for a high head site and a plan or sketch and photographs would be appropriate for a low head site, together with a few photographs, showing on the plan where they were taken.
4. Power and its end use may be for mechanical purposes i.e. water pumping, milling and driving a heat pump or an electrical generator or a combination of both. State what loads you currently use and when. Current usage and future power requirements should be given if possible.
5. The head is the distance between the normal water level at the intake point and the normal water level at the outlet point. An initial estimate of the difference in level across your land will often suffice.

The water-flow in litres or cubic metres per second is required throughout the year in order to calculate the power available, as seasonal variations in flow can be considerable. The more measurements taken over a period of time, the easier it is to select the most suitable water turbine for your site. A ‘Flow Duration Curve’ showing the number of days per year expressed as a % when a particular flow is exceeded may be available from the ‘River Authorities’.