Water Distribution System -A method for applying solar thin film for the

energy required to pump water

Group # 6Karl Patrick BullockDavid RockfordKibeum Ryoo

Students • David Rockford– B.Sc. Mechanical Engineering, UC Berkeley 2011

• Kibeum Ryoo– B.Sc. Mechanical Engineering, UC Berkeley 2010

• Karl Patrick Bullock– B.Sc. Indoor Environment & Energy, Oslo UC 2010

– Resumes enclosed

Abstract

• Solar thin film integrated on larger distribution pipes above the ground, generating electrical energy for the application of pumping fluids through the pipes. Also integrated a parabolic mirror under the pipeline for enhanced solar radiation to the thin film.

Figures

Figure 1

Figure 2

Figure 3

Description of the figures

• FIG. 1 is a perspective view of the main part• FIG. 2 is a sectional view of the tube and solar

film part• FIG. 3 is a detailed view of solar film part

Background of invention

• In areas where there is a combination of- shortage of water and high solar radiation, there is a need for electrical energy to the pumps that pump the water through the pipes. This usually requires infrastructure in the form of a electrical grid and a power plant that supplies the grid with electrical energy.

• Solar applied to the market of clean water is expected to be a $1,5 Trillion industry (Solar Trillions, Tony Seba). We will hit peak water before we hit peak oil. The aquifer that supplies water for a third of Americas food supply may dry up within two decades. Many parts of the world arte already facing a severe water crisis. But most of those regions are the ones with most sunshine falling on them.

Field of invention

• The present invention relates to a water distribution system, where a method for applying solar thin film for the energy required to pump water is integrated in the infrastructure of the distribution system itself.

Description of the Related Art • Prior arts include apparatus for using solar

energy to heat up fluid inside a tube that is surrounded by the solar energy absorber.

• Prior arts convert solar energy from the surface of a tube system to sustain desirable temperature inside via providing electricity and heating mechanism.

References Cited

• 1,946,184 Solar heater, Abbot• 4,151,828 Solar Energy Collection Tube,

Mather et al• 4,133,298 Solar heat collecting apparatus,

Hayama et al

Objects and Advantage of the invention

• The object of the solution is to contribute to both energy conservation for fluid distribution systems, and to reduce the amount of materials and infrastructure required for the energy generation which is needed to operate the fluid distribution systems.

• The solution may be used for agricultural areas where the current solution is to use open aqueducts. The benefit of this solution will also be represented in saved area because a pipe above the ground will require a significant smaller part of land than aqueducts. Thus this will of course require that the water has a higher given velocity so the pipes will have a smaller hydro dynamical cross section than the aqueducts.

Detailed description

Solar thin film is connected to the outer surface of a fluid distribution pipe. This is connected either with a combination of primer and glue, or mechanically, or in a combination of the solutions mentioned above.

• The solar radiation energy that hits the solar thin film will further be converted to electrical energy and available for the application of work to the pump shaft, electricity to the controls, and to supply the battery.

• The electricity produced will have to be regulated to a proper current and regulated with a PID controller to regulate the flow.

• The overproduction of current in peak hours, will supply a battery, which is stationed at each singular pump station. This energy will then later be available to use in other parts of the day.

• The regulator will be connected to a wireless communication transmitter, which communicates to a process communication central through a satellite.

• The electrical energy will be applied to drive the pump motor, which further rotates the pump shaft.

• The pump shaft will have an extended connection possibility, in the case of the breakdown of the energy generation part of the system. Since the risk and consequences of this happening are pretty low, there is no use of having a backup pump installed permanently, so the pump shaft will be will connected to a diesel engine provided on site only in the case of emergency.

• The pump casing will be supplied with fluid from a fluid source through a fluid source pipe. The fluid will further flow through the pump casing in to the fluid supply pipe.

• There will be connected a flow measuring transmitter on the fluid supply pipe. The signal from the flow-measuring transmitter will be a feedback signal that goes back to the PID controller.

• The fluid supply pipe will continue to a fluid distribution center, which is likely to further serve secondary distribution centrals, which further will serve tertiary distribution centrals.

• The fluid distribution pipe naturally has to be stationed above the ground for the system to work.

• There will be used parabolic or parabolic-like mirror surfaces under the pipe to enhance the solar radiation to the solar thin film. The shape of mirror surface will be determined by the use of generic algorithms to optimize the solar radiation to the thin film.

• There is a possibility that the invention will need a continuation-in-part where the mirror surfaces that in this document are stationary, will have to be dynamic- which means that they have to be able to rotate around the pipe, as the sun hits the pipe and mirror surface in different angles in course of a day.

• The system can be regulated for both, constant or variable flow. It is possible to engineer the whole system such that the first water distribution central pool is big enough to store maximum load of the pump at all times, for a longer time period, such that the system will not need to have advanced controls nor batteries.

• Potential application is for a pipe system that desalinates water, e.g. water is pumped from a shore destination to a remote area, somewhere along the way the water is desalinated, further this water is used for a variety of purposes, e.g. in desert or semi-desert areas.

• If the water is pumped to the top of a larger tank when it is reached its secondary or tertiary distribution central (as shown in the figure below), and the water has no hydro static pressure “working” against it in the end of a long straight pipe, this will further have the positive effect of a close to zero differential pressure for the pipe line on a straight stretch.

Limitations

• There are both economical and technical limitations to the solution presented. Economical limitations are related to that the solution is applicable for infrastructure with huge investments and therefore dependent on government and large businesses to be used.

• Technical limitations are given by:

the solar radiation (200- 275 w/m2) The figure below shows the mean solar radiation received at the surface, expressed in W/m2. The global mean is 170 W/m2

the thinfilm efficiency- now max 19,9% (see figure below)Though most of the commercial production of thin film solar today has an efficiency of about 11%, this is expected to rise rapidly within few years.

the friction inside the pipes Varies with the choice of material, though it is

very a little energy loss compared to the pump energy which is required to the increase in potential energy where the pipe has different z- coordinates along its way.

the viscosity of the given fluid (e.g. water) Varies with the temperature of the water.

the pump efficiencyTypically in the area of 0.82- 0.91 for pumps in the the manner of size for this system.

the height difference on the pipelineVaries with the landscape, and is one of the most limiting factors of the system.

the electrical systems grid efficiency (though there will be very little loss, as the grid system here is vastly shorter compared to the alternative of cabling distribution pumps to a central electrical generation plant.)

the outer surface area of the pipeIf needed, this can be “manipulated” by applying a extra layer of insulation around the pipes, to increase the area.

Simplified Example Calculation

Energy required to pump < ((solar radiation energy x outer surface area of pipe x thinfilm effiency x pump effiency x system effiency ) - pressure losses within pipe to pump fluid)

Energy in:Given,• diameter of pipe= 1,2 m • outer surface area = 3,768 m2• Length of pipe= 5000 m• Solar radiation= 220 w/m2• Thin film efficiency = 0,16 E.in= 663’168 W = 663.168 kW energy available

to pump the water on a 5 km distance.

Energy out:Given, • velocity of water= 1 m/s• inside diameter of pipe= 1140 mm = 1,14 m • inner surface area= 1,0207 m2• volumetric flow rate= 1,0207 m3/s = 3674,52

m3/h• height difference of the pipe= 50m• efficiency of pump= 0,91 E.out = Shaft power= 550,17 kW energy needed

to pump the water the given distance.

Energy in > Energy out Q.E.D. -The system might have a potential.

Students Background