Week 4 - Coming Together with Research

Possible Pumps

Jet Pumps
- used to lift water from ground, via suction pipe 

- can go 25 to 150 feet deep (pretty sure they can go shallower as well)

- centrifugal pump with multiple impellers and diffusers.  Also has jet ejector.

- water passes through jet and gains velocity, but decreases pressure

- increased water speed and the decrease in pressure creates suction

- larger displacement from water to top of tank means less water is moved

- jet helps move water through a tube to the pump higher up

           

Submersible Pumps
- whole pump is submerged, motor and all. 

- does not need to worry about driving water in, it focuses on pushing it out
- impellers pass water to eye of impellers in succession. The water is then passed through a diffuser   which decreases the velocity of the water and converts it to pressure
- Pressure is increased for every impeller that it passes through

Limitations of Pumps
- To get more flow from the pump that the size of the exit of the impeller needs to be increased.
- To get more pressure, also known as head the impeller exit should be decreased
- Ultimately Horse Power is the limitation to a pumps demand.

Solar Panel Information: 

- Solar panels can be made out of different materials and therefore take up different amounts of space
- On average, single solar panels can produce 300 watts of electricity
- Solar panels can be connected to form a solar array, which maximizes current and therefore increases wattage
- Total wattage depends on:

• materials used
• size of the cell
• number of cells in each panel
• number of panels in the array

- You can have the solar panel adjust to follow the sun or stay in a fixed direction

- Typical 185 watt solar PV panel measure 808 x 1508 mm and weighs approx. 15kg

- Will need to use a controller to make sure that battery does not discharge or become overcharged

- Volt*Current= power (watts) 

- Increasing voltage can make system more efficient by reducing energy lost to resistance

- Power*number of peak sun hours in your area= watts-hours

- Three most common types of solar panels are:

• Polycrystalline Panels: made of silicon with many different crystals, efficient, should be used in areas with high sun exposure
• Monocrystalline Panels: made of single silicon crystal, more expensive but more efficient than Polycrystalline
• Amorphous Panels: flexible and easier to work with, works is all daylight conditions: in northern hemisphere, install panel facing solar sought, in southern hemisphere, install panel facing solar north, charge controllers/regulators

- Regulate voltage going into battery during the day

- Protect against battery discharge at night
- Allows more current to flow when charge is low and stops current when overcharged
- Essential if solar panel is being used
- Make sure controller is compatible with the solar panels and batteries in your system
- Batteries:

• Deep cycle batteries meant to be charged and discharged many times and are ideal for use with solar panels
• can be wired together to provide as much storage capacity as needed
• rated in amp-hours- measure of how much current battery can supply in certain number of hours

-Power Inverter- change current from DC to AC (may or may not need depending on what the pump needs)

• Modified sine wave- less expensive than pure sine wave inverters; most things in a household will run fine, but others may be damaged or not run normally
• Pure sine wave- same as AC provided by electrical company; will work for any appliance that you would normally run; will probably need >75 watts of power for pump; can use higher voltage DC pump, but you will need to wire together more than one solar panel to provide the right amount of power

Wiring Solar Panels Together:

-Depends on the voltage of the charge controller

• If the solar panel and charge controller voltage are the same, need to wire them in parallel
• If the charge controller voltage 48V and panels are 24, need to wire in series

- Must also consider the wire that will be used

• more wire means more resistance
• resistance directly proportional to length of cable
• resistance inversely proportional to cross sectional area of cable; can use the resistance in the cable to calculate the voltage drop in the system (V=IxR)