message: fix(device-registry): smart meter reads serialization
diff: @@ -10,6 +10,7 @@ import {
  ISmartMeterReadStats,
  IOrganization
  } from '@energyweb/origin-backend-core';
  +import { BigNumber } from 'ethers';
  export class Entity implements IDevice {
  status: DeviceStatus;
  @@ -123,8 +124,10 @@ export class Entity implements IDevice {
  const isFirstReading = i === 0;
  energiesGenerated.push({
  - energy: allMeterReadings[i].meterReading.sub(
  + energy: BigNumber.from(
  + allMeterReadings[i].meterReading.sub(
  isFirstReading ? 0 : allMeterReadings[i - 1].meterReading
  + )
  ),
  timestamp: allMeterReadings[i].timestamp
  });
  