Power optimization for battery powered street lighting system
View Patent ↗A network is disclosed of a plurality of outdoor lighting units. Each lighting unit comprises a light fixture, for example a LED lamp; a power generating means, such as a solar panel or a wind turbine; and a storage means for electric energy, for example a battery. The energy storage means of neighboring lighting units are connected by a conductor. An imbalance in power generation or power consumption results in a balancing current through the conductor. The balancing current equalizes the charge levels of the energy storage means in the system. In an embodiment the conductor comprises a single core wire and ground.
1. A network of a plurality of outdoor lighting units, each unit comprising:
a. a light fixture;
b. a power generating means;
c. a storage means for electric energy; and
d. a connection to ground;
wherein neighboring lighting units are distanced from each other with an amount of ground therebetween and the storage means of neighboring lighting units are connected by a conductor that consists of a wire and a connection through the ground;
wherein the conductor serves to conduct electric energy from a first storage means of a first lighting unit to a second storage means of a second lighting unit by conduction through the ground between the lighting units, so as to balance charge states of the first storage means and the second storage means; and
wherein each lighting unit further comprises a controller configured to receive signals over the conductor, and each lighting unit is adapted to additionally communicate with a neighboring lighting unit via the conductor.
2. The network of claim 1 wherein the light fixture comprises LED light sources.
3. The network of claim 1 wherein the power generating means comprises (i) a solar panel; (ii) a wind turbine; or (iii) a combination thereof.
4. The network of claim 1 , wherein the storage means for electric energy comprises a rechargeable battery.
5. The network of claim 1 , wherein the single wire comprises a double core electric wire.
6. The network of claim 1 , wherein charge states are balanced as a result of a difference in operating voltage of electric energy storage means of neighboring lighting units.
7. The network of claim 6 , wherein the conductor connecting the storage means of neighboring lighting units to perform charge state balancing does not comprise a controller.
8. The network of claim 1 , wherein the conductor comprises a means for detecting a current exceeding a predetermined threshold value.
9. The network of claim 1 , wherein the outdoor lighting units are self-sufficient.
10. The network of claim 1 , wherein the power of the power generating means is supplemented with power from an external source.
11. The network of claim 1 , wherein the lighting units are connected to the conductor by a PTC fuse.
12. The network of claim 1 , wherein each lighting unit further comprises an LED driver having a dim controller, and the LED driver is configured to receive signals communicated over the conductor by pulse modulation.
13. A network of a plurality of outdoor lighting units, each unit comprising:
a light fixture,
a power generating means,
a storage means for electric energy, and
a connection to ground;
wherein neighboring lighting units are distanced from each other with an amount of ground therebetween and the storage means of neighboring lighting units are connected by a conductor that consists of a wire and a connection through the ground;
wherein the conductor conducts electric energy from a first storage means of a first lighting unit to a second storage means of a second lighting unit by conduction through the ground between the lighting units to balance charge states of the first storage means and the second storage means; and
wherein each lighting unit comprises a controller configured to receive signals over the conductor, a driver connected to the conductor that is configured to receive signals communicated over the conductor, and each lighting unit is adapted to additionally communicate with a neighboring lighting unit via the conductor.
14. A network of a plurality of outdoor lighting units, each unit comprising:
a light fixture,
a power generating means,
a storage means for electric energy, and
a connection to ground;
wherein neighboring lighting units are distanced from each other with an amount of ground therebetween and the storage means of neighboring lighting units are connected by a conductor that consists of a wire and a connection through the ground;
wherein the conductor is arranged to conduct electric energy from a first storage means of a first lighting unit to a second storage means of a second lighting unit by conduction through the ground between the lighting units in order to balance charge states of the first storage means and the second storage means;
wherein each lighting unit comprises a controller configured to receive signals over the conductor and is further configured to transmit digital information over the conductor and/or to communicate with a neighboring lighting unit via the conductor by pulse modulation; and
wherein each lighting unit is adapted to additionally communicate with a neighboring lighting unit via the conductor.