DC GRID TECHNOLOGY. Our DC grid components offer the most efficient and cost effective option for rural energy access at locations with high building density.


SMART DC GRID. SMART FEATURES.

 

BOS PT - DC GRID SIGNAL TRANSMITTER

BOS PM - DC GRID SMART POWER METER


DC GRIDS ARE THE MOST EFFICIENT AND COST EFFECTIVE OPTION FOR RURAL ENERGY ACCESS AT LOCATIONS WITH HIGH BUILDING DENSITY AND FOR RESIDENTAL HOMES WITH RENTED OUT ROOMS.


For setting up a smart DC-grid two components are needed (next to a solar home system as central energy hub). Power meters at each household and a grid signal transmitter at each energy hub. Both products, the PM10 and the PT20, share the same housing, but have different functionalities and features.

PM PT Bild


STRUCTURE OF A DC GRID WITH POWER METERS AND POWER TRANSMITTERS

 

1 CENTRAL ENERGY STATION
A central energy station, equipped with a solar home system and the BOS PT grid signal transmitter forms the central unit of a SMART DC Grid. The central energy station can be any 12 VDC lead acid solar home system, hybrid systems from BOS are recommended.

 

 

2 DC GRID CONNECTED HOUSEHOLDS
Individual households /users, each one equipped with the BOS PM smart power meter, are DC grid connected with the central energy station.

 

 BOS PM10 PT10 haus Grafik3

3 INTELLIGENT POWER TARIFFS
The PT transmitter communicates through signals with the PM power meters. Power tariffs are less expensive during daytime and more expensive during night time. During times of excess energy in the grid the tariffs get cheaper, and respectively more expensive during times of low energy levels.

4 INTELLIGENT LOAD MANAGEMENT
The SMART DC grid switches excess energy loads and emergency lights automatically. Once the state of charge of the DC grid reaches full level, each meter automatically switches on a separate excess energy load output. This excess energy output powers big loads only during times of excess energy when tariffs are cheap, hence households optimize their energy costs. Once the state of charge of the DC grid reaches a low level, all loads are automatically disconnected. If users finish their daily energy quota, they can still use an emergency light.


 COST COMPARISON DC MINI GRID VS. AC DIESEL GRID

The DC grid operator employs a workable business model, which has been proven to be effective over decades of use in AC diesel grids. With reasonable hardware costs, maintenance that is close to zero and no generation costs, DC grids are the superior solution compared to AC grids.


ACCOUNTS COMPARISON DC MINI GRID VS. AC DIESEL GRID

Stand-alone DC grids offer an inexpensive way to achieve energy access for all. Initial investment costs per household are very low. Through the sales of energy to DC grid connected households, a continuous cash flow is achieved for the grid operator. Individual households pay as much as they did before for a significantly improved energy service.


SMART PAYMENT MODELS

The meter counts the user’s energy quota downwards until it reaches level zero. Then it turns off the loads until a reset signal from the grid sets the meter level back to a high value. This reset signal occurs on a regular basis, depending on the grid operator. Users can choose different energy quotas and pay accordingly.


SELL ENERGY TO ROOMS / IMPROVE ROI

In residential homes with rented out rooms, hotels or buildings with several flats, DC mini grids can be employed to provide energy to each user based on individual tariffs. In case a bigger solar system is already available return on investment can be improved significantly by selling energy to neighbours.


PM10 & PT20 KEY TECHNICAL SPECIFICATIONS

Characteristic

PM10 PT20

Role in DC grid

DC power meter at

each user

Feed-in power transmitter at

each energy station

Nominal System Voltage

12VDC 12VDC

Max. load output current

 5A (10A peak) 20A

Integrated USB charging port

1 port 5V/1A 1 port 5V/1A

Size housing

130x100x75mm 130x100x75mm

Weight

 350g 350g

Recommeded wiring small grid

(e.g. in-house @ residential homes)

4mm² 3 phase cables, max. 20m radius

around Power Transmitter

Recommeded wiring extended village grid

 10mm² 3 phase cables, max. 50m radius

around Power Transmitter

 


 SMART DC GRID SIZING EXAMPLES