Claims:1. System configuration claims.
The Smart Solar energy home system with intelligent energy management comprising of three main components as indicated in figure 1,
The energy manager with solar panel, electronic microprocessor based buck charger, communication module to implement the communication bus protocol and energy manager algorithm.
The next component consists of communication bus indicated in figure 5, is a three-wire bus consisting of a power bus, data line which switches between 0 and 5 volts.
Intelligent points: Intelligent points microprocessor based electronic which are connected to the communication bus. They draw power from the bus and take action based on the commands received from the energy manager in form of data packets either turn ON or OFF or DIM a lamp.
2. System method claims.
2a. The energy manager as claimed in claim 1, divides usage of energy by intelligent points on the communication bus into sub intervals. Each point is assigned a priority and a utilisation factor is calculated by the energy manager based on which the intelligent points are controlled. The utilisation factor is calculated by the formula (hours of energy used in a day) divided by 24 Hrs and then multiplied by 100. The intelligent points send to the energy manager change in their status ON or OFF. This status is maintained in the energy manager software along with the priority and utilisation factor. The highest priority points is assigned maximum sub interval ON time SIOT and sub interval DIM time SIDT. The maximum SIOT is 90 minutes ON time and SIDT of 30 minutes 75% dim time (for dimmable points) for a total sub interval time SIT of 2hrs. The intelligent point shall go off automatically once SIOT is complete. The user presses the ON button on the intelligent point to extend the SIOT. This ensures that unless the energy is required and user places a new request of ON the intelligent point will go off automatically to stop wastage of energy. In a home with five rooms, one of the rooms would be a wash room. The wash room would require shorter SIT of 15 minutes with SIOT of 10 minutes and SIDT of 5 minutes. Thus assigning different SIT to different intelligent points with auto turn off results in reducing wastage of energy. Further the energy manager continuously monitors and calculates the charge level in the energy storage battery by monitoring the charge current from the solar panel and the current drawn by the communication Bus. Based on the charge level and the Utilisation factor UF the hours its known how many hours of energy each intelligent point will need for that day. (UF x 24 minus hours already used) x current for that point. The rating of each intelligent point is known. Thus the total future day needs can be calculated. If the charged status battery is less than the future energy needs. Its necessary to shut off low priority and low utilised intelligent points. This is done automatically by energy manager by sending the OFF command over the communication link to the point to be put OFF. If a low priority point such as a wash room light is required to put ON. The user presses the ON button on the point. The point turns ON for the SIOT time and switches OFF automatically after the SIT time. The energy manager will automatically switch off the next least important point based on Priority, person presence in room sensor status and UF.
2b. Configuration is the process of setting priorities for the intelligent points. The priority of an intelligent point is set by pressing the ON button for 10 seconds. The configuration mode is indicated by flashing of lamp or LED (light emitting diode) twice. After a gap of minimum 2 seconds, the button is then pressed ON for 2 seconds and with gaps of two seconds pressed ON again. If the priority is to be set for three the button is pressed thrice with gaps of 2 seconds. Each press of button is acknowledged by blinking of the LED. Similarly for priority 5 the button is pressed five times. The configuration mode is completed by pressing the button for 10 seconds. Then the point sends a request for priority assignment to the energy manager along with the type of point it is and its energy rating such as 18 watts for LED lamps. The default address for the configuring point is Sa = 253 decimal (0xFD). At a time only one point shall be configured. From this the energy manager calculates the current requirements to the point and sets the priority and assigns an address to the point. The point shall receive an acknowledgement message from the energy manager for the configuration request. The Acknowledge message to the point will contain the address the point is assigned. This is done for every point. The system has a maximum of 5 priorities. By default the priority is set to one. Each priority is assigned the sub interval time (SIT) time. Priority 1 has SIT of 15 minutes, sub interval ON time SIOT of 10 minutes and sub interval dim time SIDT of 5 minutes. Priority two has SIT of 30 minutes, SIOT of 25 minutes and SIDT of 5 minutes. Priority three has SIT of one hour, SIOT of 50 minutes and SIDT of 10 minutes. Priority 4 has SIT of 2 hours, SIOT of 90 minutes and SIDT of 30 minutes and Priority 5 has SIT 8 hours, SIOT of 7 hrs and SIDT of 1 hrs. SIOT is sub interval ON time and SIDT is sub interval Dim time when output is set to 75% level. The SIT, SIOT and SIDT and SIDT levels shall be settable at time of manufacturing. The points when active ON shall remain ON for the SIOT time and dim for the SIDT time and then turn off automatically without energy manager’s intervention. The user could press the ON button on the point any time to turn OFF the point and then press the button again to activation a new SIT time and turning ON the Point.
2c. The Messages between the Energy manager and the points shall be in the form of packets made up of a string of asynchronous 8 bit data byte having additionally one start bit, no parity and two stop bits. The Format of the packet is as below.

[ Da Sa C DC Dd Dd Dd… CS]
[ = start delimiter of message packet with 250 ms minimum blank HIGH signal on BUS as separation between messages.
Da = single 8 bit byte destination address destination of packet.
Sa = single 8 bit byte source address from where the packet is sent.
C = Command Byte 8 bit for action to be taken
DC = data byte count to follow.
Dd = Data byte 8 Bit.
CS = simple check sum
] = end packet delimiter.
Reserved Destination and source addresses
0 is a reserved source and destination address of the Energy manager.
254 decimal ( 0x FE) source address of configurator programmer.
255 decimal ( 0xFF) broadcast address.

The types of command bytes and respective data packet formats are as follows:
1. 0xFE - Set priority C = 0xFE DC =0x03 Dd = type Dd = watts Dd = priority

2. 0x10 - Point(lamp)status C= 0x10, DC =0x01 Dd = 0x00 (OFF) else 0x01 (ON)

3. 0x20 - Lamp command C= 0x20 DC = 0x01 Dd = 0x00 (OFF) 0x01 ON and 1 t0 100 dim levels. That is 0x01 to 0x64 )x64 is for 100% illumination.

4. 0x30 - ACK packet for last sent packet 0x00 Nack indicates error in message received and 0x01 is ACK message received OK.

5. 0x40 - Presence sense status C=0x40 DC=0x01 Dd = 0x00 (no presence) Dd =0x01 (presence)

6. 0x50 - Configuration Ack C = 0x50 DC =0x02 Dd = address point(PA) Dd = priority number (PN).

7. 0x11 - Point presence sensor C= 0x11, DC =0x01 Dd = 0x00 (OFF) else 0x01 (ON) Presence of a person in a room.

8. Rest of the bytes (8 to 250) are future reserved commands.
Point types:
Points (Figure 3) are devices on the bus which receive power from the Energy manager and implement the above mentioned protocols. The device could be any device which operates on the bus voltage. This could be a Led lamp [601], a TV [603] or FAN [602], etc.
2d. The communication and power bus shall be a three-wire system. Wire 1 [401] carries voltage of 12v, or 24volts or 48 volts and shall be a red colour wire. Higher rating system shall operate at higher voltages. Wire 2 [402]of the system will be blue colour and will operate between 5 volts and 0 Volts with third wire shall be reference GND wire 0V [403].
, Description:Field of invention: Solar energy management.
Background:
According to World Bank, 15% of world population does not have access to electricity that is 1.1 billion people. Most of these people live in rural areas without access to power grids. Rural electrification has been a major challenge for a country as big as India. Even though in the recent past the target of electrifying every village has been achieved, it hasn't powered every household in those villages. Some households who are beneficiaries of the new connection are facing routine problem of load shedding or frequent power outages. There is a heavy infrastructural requirement in order to achieve the goal of uninterrupted power supply. In addition to that, problem arises due to geographical constraints of those villages. There are many hurdles that are needed to be crossed in order to fulfil the requirements of a comprehensive rural electrification. Solar energy provides an opportunity for such rural population for access to electricity. We also find that in many developed countries people are adopting solar energy due to costs of grid power. Grid net metering provides an opportunity to reduce cost of power.

Object of invention:
This invention focuses on a solution for lighting in rural homes and the idea can also be expanded to urban homes. The challenge in solar systems is to manage the use of solar energy which is captured and stored in batteries. The energy captured is variable and depends on the weather conditions and managing energy can be very challenging, this prerequisites for a system with intelligent management of available green energy. The second challenge is to reduce the cost of deploying off-grid systems in rural areas. The solar systems need to be affordable and simple. This invention focuses on these challenges.

Summary:
Purpose of invention:
• Circuit complexity is less as well as the cost which will be in the range affordable to rural homes.
• Implementing a system which adapts itself depending on the requirements of the end user as well as the available stored energy.
• Energy levels are assigned to each room, based on the priorities set by the user. This priority assignment, along with additional optimization provided by sub interval time (SIT) lighting, enhances the utility of energy.

Figure 1 illustrates the schematic of the whole system.
Figure 2 illustrates the block diagram of the energy manager.
Figure 3 illustrates the schematic of communication and power BUS.
Figure 4 illustrates the Schematic of point.
Figure 5 illustrates the table of typical lighting load requirement of a rural home.
Figure 6 Points and point type.

System configuration:
The system consists of the central energy manager [102], solar panel [101], intelligent points [103] which include, intelligent lighting lamp [104], controllable power points for devices such as fan [105], TV [106], etc., and three wire communication buses [107]. Figure1 shows the systematic of the system. The novelty of the system is the three-wire bi-directional communication bus system and the energy manager algorithm method.
The Energy Manager:
The energy manager figure2 consists of a microcontroller [206], a buck converter solar charger [202], solar panel [201], battery [207], charge controller software [203], energy manager software [205], and communication protocol [204] which communicates over a three wire bus [208].
1. Energy manager control algorithm:
The Novelty of the invention is in the energy manager along with the special communication protocol which is compact and efficient. The energy manager software monitors the charge and discharge of the battery which stores the energy and therefore, the charge stored in the battery given by, IxT. I, is current into the battery and T, is the time in seconds.

Each point is assigned a priority during the configuration process at time of installation of the system. The configuration process is explained later in this document.

Figure 6 gives a typical example of the lighting requirements of a rural home. The Lights are taken to be LED lamps of 18 watts which is approximately equivalent to 40 watts incandescent lights. The home has a living room, a kitchen, two bedrooms and a wash room. The living room is most used and the lighting is required for 8 hours typically between 6 pm and 12 pm and 6 am to 8 am. The kitchen requires light for 4 hours. Bedrooms require light for 4 hours each. The wash room requires light for approximately 30 minutes for each use and it is assumed that the bathroom will be used 6 times a day. The maximum energy requirement is found to be 366 watts hours or 30.5 AH at 12 volts battery. This is the maximum requirement ideally. It may so happen that due to poor weather the battery may not get 30.5 AH charge during the day. Therefore the challenge is to utilise the available charge AH (Ampere Hours).
The way to utilise the energy effectively is to prioritise the points/lamps and switch ON or OFF the lamps when energy levels are low. From Figure 6 it is observed that
a) When charge level is greater than 80% all lamps to be used.
b) When charge levels are greater than 60% and less than 80% all lamps to be used.
c) When charge levels are greater than 40% and less than 60% all lamps to be used except washroom lights could be ON.
d) When charge levels are greater than 20% and less than 40% all lamps to be used except washroom lights could be ON.
e) When charge levels are greater than 10% and less than 20% only living room high priority node will be ON.
f) Below 10% or below the minimum safe battery voltage the system with turn OFF and go into sleep mode.

The use of energy is further optimised by using light for a fixed sub interval ON time SIOT. The system has a maximum of 5 priorities. By default the priority is set to one. Lowest priority is one and 5 is the highest priority. Each priority is assigned the sub interval time (SIT) time. Priority 1 has SIT of 15 minutes, sub interval ON time SIOT of 10 minutes and sub interval dim time SIDT of 5 minutes. Priority two has SIT of 30 minutes, SIOT of 25 minutes and SIDT of 5 minutes. Priority three has SIT of one hour, SIOT of 50 minutes and SIDT of 10 minutes. Priority 4 has SIT of 2 hours, SIOT of 100 minutes and SIDT od 10 minutes and Priority 5 has SIT 8 hours, SIOT of 7 hrs and SIDT of 1 hrs. SIOT is sub interval ON time and SIDT is sub interval Dim time when output is set to 75% level. The SIT, SIOT and SIDT and SIDT levels shall be settable at time of manufacturing. The points when active ON shall remain ON for the SIOT time and dim for the SIDT time and then turn off automatically without energy manager’s intervention. The user shall press the ON button on the point any time to turn OFF the point and then press the button again to activate a new SIT time assigned to its priority and turning ON the Point. From the above each node is assigned a priority, full on period, low intensity period and then OFF.

The above is illustrated for a system with five Lamps. However five lamps is not a limiting factor for this system. There could be larger systems with higher AH, wattage, and number of devices, these devices could be Lamps or fans or TV etc. During installation the Priority, Full On period, Dim period, will be configured into the charger, via a communication link either wireless or wired network.

The energy manager receives status of every point whether ON or OFF and DIM levels over the Communication bus. This status information is used to derive how long the devices were ON. This provides information to the energy manager to arrive at which points/lamps are most commonly used. The Utilisation factor UF criteria for every point is calculated and ranked of every device. UF is used to decide which device is to be put OFF, when energy is to be conversed and optimally used when available charge in battery is Low. The UF factor is calculated by formula ((number of hours device is used)/ 24 Hrs))* 100. The UF factor of previous three days is taken to get average UF factor. UF indicates which devices are commonly used. Device with lower UF but higher priority could be replaced by a device with lower priority. The system shall support person presence sensors. If person is not present in a room, the point shall inform the energy manager that the room is not occupied and the light could be put OFF. The points shall be programmed to go off automatically. By default the time to turn OFF light if room is not occupied shall be ten minutes.

Example if the battery charge level is between 40% and 20% and the highest priority lamps needs to be On. If the washroom light is needed the user puts on the washroom light. The system then searches for the device with higher priority but least UF. The system puts OFF the lamp with higher priority and lower UF and keeps the washroom light ON for sub interval ON time SIOT = 10 minutes and Sub interval dim time SIDT= 5 minutes.

The central process in this innovation is to conserve energy and use the saved energy for the next day. In regular solar energy systems the battery and solar panels are oversized. Typically the batteries and solar panels are designed to provide for two days. This results in costlier system size. By reducing the battery capacity and solar panel to 1.5 days requirement, the cost reduces considerably. Additional use of intelligent energy manager can enhance the utilisation of the energy.

2. Buck solar charger:
The solar charger is a buck charger consisting of MOSFET power device and related driver circuit. The buck convert is controlled by the PWM signal from the microcontroller. The software on the microcontroller controls the charging of the battery as per the profile of the battery used. The microcontroller also maintains the status of charge of the battery by continuously time integrating the current flowing into and out of the battery. The total charge stored in the battery at any time is used by the energy manager software to determine which lamp ON requests could be maintained.

3. Communication Module:
The Communication module in the energy manager controls the function of message communication between the energy manager and the different points/lights. The messages are sent from and to the points. The communication protocol is explained in the section on Communication and power Bus.
4. Communication and power bus:
The energy and communication between energy manager and points/lights happens over the communication bus. The bus is a three-wire system as shown in figure4. Wire1 [401] carries voltage of 12v, or 24volts or 48 volts and shall be a red colour wire. Higher rating system shall operate at higher voltages. Wire 2 [402] of the system will be blue in colour and will operate at 5 volts. The third wire will be reference GND wire [403].

The data is transmitted using the standard asynchronous one start bit 8 bit data no parity and two stop bits. The basic characteristic of this system for data communication are, the volume of data is low. There may be an average of one request from the points to the energy manager per hour to either turn on or turn off the lights. For a five lights system this would mean five requests per hour. The therefore the time gap between requests is large. This means that the baud rate requirements of the system are very low. 600 baud or 300 baud could easily be used and therefore data could be transmitted over larger distances. The data packet format is also optimised. The format of the packet is as follows.

[ Da Sa C DC Dd Dd Dd… CS]

[ = start delimiter of message packet with 250 ms minimum blank HIGH signal on BUS as separation between messages.

Da = single 8 bit byte destination address destination of packet.

Sa = single 8 bit byte source address from where the packet is sent.

C = Command Byte 8 bit for action to be taken

DC = data byte count to follow.

Dd = Data byte 8 Bit.

CS = simple check sum

] = end packet delimiter.

Reserved Destination and source addresses

0 is a reserved source and destination address of the Energy manager.

253 decimal (0xFD) default point configuration address

254 decimal ( 0x FE) source address of configurator programmer.

255 decimal ( 0xFF) broadcast address.

The types of command bytes and respective data packet formats are as follows:
1. 0xFE - Set priority C = 0xFE DC =0x03 Dd = type Dd = watts Dd = priority

2. 0x10 - Point(lamp)status C= 0x10, DC =0x01 Dd = 0x00 (OFF) else 0x01 (ON)

3. 0x20 - Lamp command C= 0x20 DC = 0x01 Dd = 0x00 (OFF) 0x01 ON and 1 t0 100 dim levels. That is 0x01 to 0x64 )x64 is for 100% illumination.

4. 0x30 - ACK packet for last sent packet 0x00 Nack indicates error in message received and 0x01 is ACK message received OK.

5. 0x40 - Presence sense status C=0x40 DC=0x01 Dd = 0x00 (no presence) Dd =0x01 (presence)

6. 0x50 - Configuration Ack C = 0x50 DC =0x02 Dd = address point(PA) Dd = priority number (PN).

7. 0x11 - Point presence sensor C= 0x11, DC =0x01 Dd = 0x00 (OFF) else 0x01 (ON) Presence of a person in a room.

8. Rest of the bytes (8 to 250) are future reserved commands.

5. Points:
Points (Figure 3) are devices on the bus which receive power from the Energy manager and implement the above mentioned protocols. The points consist of communication software [302], microprocessor [303], switch control software [304] control electronics [305] and device [306].The device could be any device which operates on the bus voltage. This could be a Led lamp [601], a TV[603] or FAN[602], if the system supports the rating. Each of the point devices are given a type number mentioned below. The devices are connected to the bus via an intelligent point which is controlled by the protocol. In a lamp the intelligent point could be a part of the lamp itself. For a Fan the Fan would be connected to the bus via an intelligent point which turns on or off the fan. The intelligent point variable point shall give a variable output of 0 to bus Power voltage- 1 volt. An intelligent point Switch shall switch output power ON of OFF to power devices like TV.

6. Configuration:
Configuration is the process of setting priorities for the intelligent points. The priority of an intelligent point is set by pressing the ON button for 10 seconds. The configuration mode is indicated by flashing of lamp or LED (light emitting diode) twice. After a gap of minimum 2 seconds, the button is then pressed ON for 2 seconds and with gaps of two seconds pressed ON again. If the priority is to be set for three the button is pressed thrice with gaps of 2 seconds. Each press of button is acknowledged by blinking of the LED. Similarly for priority 5 the button is pressed five times. The configuration mode is completed by pressing the button for 10 seconds.

Then the point sends a request for priority assignment to the energy manager along with the type of point it is and its energy rating such as 18 watts for LED lamps. The default address for the configuring point is Sa = 253 decimal (0xFD). At a time only one point shall be configured. From this the energy manager calculates the current requirements to the point and sets the priority and assigns an address to the point. The point shall receive an acknowledgement message from the energy manager for the configuration request. The Acknowledge message to the point will contain the address the point is assigned.

This is done for every point. The system has a maximum of 5 priorities. By default the priority is set to one. Each priority is assigned the sub interval time (SIT) time. Priority 1 has SIT of 15 minutes, sub interval ON time SIOT of 10 minutes and sub interval dim time SIDT of 5 minutes. Priority two has SIT of 30 minutes, SIOT of 25 minutes and SIDT of 5 minutes. Priority three has SIT of one hour, SIOT of 50 minutes and SIDT of 10 minutes. Priority 4 has SIT of 2 hours, SIOT of 90 minutes and SIDT of 30 minutes and Priority 5 has SIT 8 hours, SIOT of 7 hrs and SIDT of 1 hrs. SIOT is sub interval ON time and SIDT is sub interval Dim time when output is set to 75% level. The SIT, SIOT and SIDT and SIDT levels shall be settable at time of manufacturing. The points when active ON shall remain ON for the SIOT time and dim for the SIDT time and then turn off automatically without energy manager’s intervention. The user could press the ON button on the point any time to turn OFF the point and then press the button again to activation a new SIT time and turning ON the Point.