LINK
Look promising and have 433mhz transmitter.



Specification:
1) Accuracy: ≤5%
2) Measuring current: 100mA-70A Measuring range: 10W~17.5KW
3) Voltage setting: 100~250v AC
4) Transmitter sample rate: 2s, 8s, 64s
5) Transmission frequency: 433.92MHz
6) Carbon ration: 0.5kg CO2/KWH
7) Power supply: 3pcs AA for receiver(battery not include); 3pcs AA for transmitter (battery not include)
8) Wireless transmitting range:30m-70m insight.
9) Operating Temperature: -10oC~ 60 oC Storage Temperature: -20 oC ~75 oC