<P> There are numerous sets of instructions for making lemon batteries and for obtaining components such as light - emitting diodes ( LEDs ) , electrical meters ( multimeters ) , and zinc - coated ( galvanized ) nails and screws . Commercial `` potato clock '' science kits include electrodes and a low - voltage digital clock . After one cell is assembled , a multimeter can be used to measure the voltage or the electric current from the voltaic cell ; a typical voltage is 0.9 V with lemons . Currents are more variable , but range up to about 1 mA ( the larger the electrode surfaces , the bigger the current ) . For a more visible effect , lemon cells can be connected in series to power an LED ( see illustration ) or other devices . The series connection increases the voltage available to devices . Swartling and Morgan have published a list of low - voltage devices along with the corresponding number of lemon cells that were needed to power them ; they included LEDs , piezeoelectric buzzers , and small digital clocks . With the zinc / copper electrodes , at least two lemon cells were needed for any of these devices . Substituting a magnesium electrode for the zinc electrode makes a cell with a larger voltage ( 1.5 − 1.6 V ) , and a single magnesium / copper cell will power some devices . Note that incandescent light bulbs from flashlights are not used because the lemon battery is not designed to produce enough electric current to light them . By multiplying the average current of a lemon ( 0.001 A / 1mA ) by the average ( lowest ) voltage ( potential difference ) of a lemon ( 0.7 V ) we can conclude that it would take more than 6 million lemons to give us the power of an average 4320W car battery . </P>
<P> There are numerous sets of instructions for making lemon batteries and for obtaining components such as light - emitting diodes ( LEDs ) , electrical meters ( multimeters ) , and zinc - coated ( galvanized ) nails and screws . Commercial `` potato clock '' science kits include electrodes and a low - voltage digital clock . After one cell is assembled , a multimeter can be used to measure the voltage or the electric current from the voltaic cell ; a typical voltage is 0.9 V with lemons . Currents are more variable , but range up to about 1 mA ( the larger the electrode surfaces , the bigger the current ) . For a more visible effect , lemon cells can be connected in series to power an LED ( see illustration ) or other devices . The series connection increases the voltage available to devices . Swartling and Morgan have published a list of low - voltage devices along with the corresponding number of lemon cells that were needed to power them ; they included LEDs , piezeoelectric buzzers , and small digital clocks . With the zinc / copper electrodes , at least two lemon cells were needed for any of these devices . Substituting a magnesium electrode for the zinc electrode makes a cell with a larger voltage ( 1.5 − 1.6 V ) , and a single magnesium / copper cell will power some devices . Note that incandescent light bulbs from flashlights are not used because the lemon battery is not designed to produce enough electric current to light them . By multiplying the average current of a lemon ( 0.001 A / 1mA ) by the average ( lowest ) voltage ( potential difference ) of a lemon ( 0.7 V ) we can conclude that it would take more than 6 million lemons to give us the power of an average 4320W car battery . </P>
how much electricity does a lemon battery produce
how much electricity does a lemon battery produce
0.9 V
0.9 V