Hoymiles Zero Export script

10-10-20

A bit niche, but this might be in someone's interest.

A gent called Tobias Kraft released a script which can be used to manage a zero-export configuration on a microinverter solar solution. It's mainly aimed at the balcony solar market where the amount of energy generated is not enough to want to move to a feed-in tariff plan. The objective of the script is to manage the output of the inverters to closely match or follow the local power demand so that the system has very limited export to the grid. It does this by turning up or down the level of power generated from each inverter using a script which writes to each inverter through OpenDTU.

It's easy enough to deploy in a docker environment, but the initial config is quite involved and you need to have a compatible power meter (such as a Shelly EM) on the network.

https://github.com/reserve85/HoymilesZeroExport

root@gp-docker:/opt/HoymilesZeroExport# git clone https://github.com/reserve85/HoymilesZeroExport

Before running in docker, I gave it the required HoymilesZeroExport_Config_Override.ini file with the following params:

[COMMON]
# Number of Inverters
INVERTER_COUNT = 3
# max difference in percent between SetpointLimit change to approximate the power to new setpoint
SLOW_APPROX_LIMIT_IN_PERCENT = 20
# if slow approximation: additional limit based on the limit-difference to "smoot the curve": newLimitSetpoint = newLimitSetpoint + (LimitDifference * SLOW_APPROX_FACTOR_IN_PERCENT / 100)
SLOW_APPROX_FACTOR_IN_PERCENT = 20
# interval time for setting limit to Hoymiles
LOOP_INTERVAL_IN_SECONDS = 10
# Timeout time to wait for Acknowledge after sending limit to Hoymiles Inverter
SET_LIMIT_TIMEOUT_SECONDS = 10
# polling interval for powermeter (must be <= LOOP_INTERVAL_IN_SECONDS)
POLL_INTERVAL_IN_SECONDS = 1
# if your powermeter exceeds POWERMETER_MAX_POINT: immediatelly set the limit to predefined percent of HOY_MAX_WATT (if you have more than one inverter it´s the sum of all HOY_MAX_WATT)
# value = 0 disables the feature. Values are possible from [0 to 100]
ON_GRID_USAGE_JUMP_TO_LIMIT_PERCENT = 100
# if your powermeter falls below POWERMETER_MIN_POINT: immediatelly decrease the limit
ON_GRID_FEED_FAST_LIMIT_DECREASE = false
# max difference between Limit and real output power in % of HOY_MAX_WATT (100 = disabled)
# which limits the limit from increasing even if no more can be produced (not enough sun). Otherwise the limit will constantly run towards 1500W, but the inverter will hover around 300W.
MAX_DIFFERENCE_BETWEEN_LIMIT_AND_OUTPUTPOWER = 10
# enable logging to file
ENABLE_LOG_TO_FILE = true
# how many logfiles you wish to keep
LOG_BACKUP_COUNT = 30
# defines how often the Inverter Power Status will be set, set it to "-1" for disabled (infinite repeat)
SET_POWERSTATUS_CNT = 10
# log the inverter temperature
LOG_TEMPERATURE = false
# delay time after turning the inverter off or on
SET_POWER_STATUS_DELAY_IN_SECONDS = 10
# define if you want to set your inverter to min-limit when your powermeter can't be read out
SET_INVERTER_TO_MIN_ON_POWERMETER_ERROR = true
# Total number of retries to allow.
MAX_RETRIES = 10
# A set of integer HTTP status codes that we should force a retry on. Don´t change unless you know what you are doing
RETRY_STATUS_CODES = 500,502,503,504
# It allows you to change how long the process will sleep between failed requests. The algorithm is as follows: {backoff factor} * (2 ** ({number of total retries} - 1))
RETRY_BACKOFF_FACTOR = 0.1


[CONTROL]
# --- global defines for control behaviour ---
# POWERMETER_TARGET_POINT is the target power for powermeter in watts
POWERMETER_TARGET_POINT = -30
# POWERMETER_TOLERANCE is the tolerance (pos and neg) around the target point. in this range no adjustment will be set
POWERMETER_TOLERANCE = 25
# POWERMETER_MAX_POINT is the maximum power of your powermeter for the normal "regulation loop".
# if your powermeter jumps over this point, the limit will be increased instantly. it is like a "super high priority limit change".
# if you defined ON_GRID_USAGE_JUMP_TO_LIMIT_PERCENT > 0, then the limit will jump to the defined percent when reaching this point.
POWERMETER_MAX_POINT = 0
# POWERMETER_MIN_POINT is the minimum power of your powermeter for the normal "regulation loop".
# if your powermeter jumps under this point, the limit will be reduced instantly. it is like a "super high priority limit change".
POWERMETER_MIN_POINT = -500

# List of INVERTERS, based on COMMON/COUNT
[INVERTER_1]
# Name: hm350-office
# serial number of your inverter, if empty it is automatically read out of the API. If you have more than one inverter you should define the serial number here (prevents mix-up).
SERIAL_NUMBER = 112183214420
# enable (true) / disable (false) this inverter
ENABLED = true
# manufacturer power rating of your inverter.
HOY_INVERTER_WATT = 350
# max. power output of your inverter (e.g. if you have a 1500W Inverter and you only want to output max. 1000W)
HOY_MAX_WATT = 350
# minimum limit in percent, e.g. 5% of your inverter power rating
HOY_MIN_WATT_IN_PERCENT = 15

Then watch the output by looking as the log output using docker:

root@gp-docker:/opt/HoymilesZeroExport# docker container ls

CONTAINER ID   IMAGE                                       COMMAND                  CREATED       STATUS                  PORTS                    NAMES

dee62f17ffe9   ghcr.io/reserve85/hoymileszeroexport:main   "/venv/bin/python3 H…"   8 hours ago   Up 8 hours                                       hoymileszeroexport


root@gp-docker:/opt/HoymilesZeroExport# docker logs -f dee62f17ffe9
2024-09-02 18:59:48 INFO     powermeter ShellyEM: 969 Watt

2024-09-02 18:59:48 INFO     Inverterlimit was already accepted at 1850 Watt

2024-09-02 18:59:58 INFO     OpenDTU: Inverter "hm350-office" reachable: True

2024-09-02 18:59:59 INFO     OpenDTU: Inverter "hm800-office" reachable: True

2024-09-02 18:59:59 INFO     OpenDTU: Inverter "hm700-shed" reachable: True

2024-09-02 18:59:59 INFO     powermeter ShellyEM: 1001 Watt

2024-09-02 18:59:59 INFO     Inverterlimit was already accepted at 1850 Watt

2024-09-02 19:00:09 INFO     OpenDTU: Inverter "hm350-office" reachable: True

2024-09-02 19:00:09 INFO     OpenDTU: Inverter "hm800-office" reachable: True

2024-09-02 19:00:09 INFO     OpenDTU: Inverter "hm700-shed" reachable: True

2024-09-02 19:00:09 INFO     powermeter ShellyEM: 975 Watt

2024-09-02 19:00:09 INFO     Inverterlimit was already accepted at 1850 Watt

2024-09-02 19:00:19 INFO     OpenDTU: Inverter "hm350-office" reachable: True

2024-09-02 19:00:19 INFO     OpenDTU: Inverter "hm800-office" reachable: True

2024-09-02 19:00:19 INFO     OpenDTU: Inverter "hm700-shed" reachable: True

2024-09-02 19:00:20 INFO     powermeter ShellyEM: 981 Watt

I'm waiting for a sunny day to see how well it follows the changes in demand in my house.

Jonathan

But there should be no need for this in Ireland as everyone has submitted an NC6 for all their inverters, right? 😂

10-10-20

https://www.boards.ie/discussion/comment/122576190#Comment_122576190

It's just for while you wait for your NC6 to be drawn up. 😀

10-10-20

It's working pretty well. It's hovering around an export of 50w and adjusting every 10 seconds.

2024-09-03 14:46:51 INFO     powermeter ShellyEM: -41 Watt

2024-09-03 14:46:52 INFO     powermeter ShellyEM: -71 Watt

2024-09-03 14:46:53 INFO     powermeter ShellyEM: -49 Watt

2024-09-03 14:46:54 INFO     powermeter ShellyEM: -73 Watt

2024-09-03 14:46:55 INFO     powermeter ShellyEM: -55 Watt

2024-09-03 14:46:56 INFO     powermeter ShellyEM: -60 Watt

2024-09-03 14:46:57 INFO     powermeter ShellyEM: -26 Watt

2024-09-03 14:46:58 INFO     powermeter ShellyEM: -69 Watt

2024-09-03 14:46:59 INFO     powermeter ShellyEM: -43 Watt

2024-09-03 14:47:00 INFO     powermeter ShellyEM: -61 Watt

2024-09-03 14:47:02 INFO     intermediate meter OpenDTU: 452 Watt

2024-09-03 14:47:02 INFO     overproducing: reduce limit based on actual power

2024-09-03 14:47:02 INFO     setting new limit to 427 Watt

2024-09-03 14:47:02 INFO     OpenDTU: Inverter "hm350-office": setting new limit from 350 Watt to 80 Watt

2024-09-03 14:47:12 INFO     OpenDTU: Inverter "hm350-office": Limit acknowledged

2024-09-03 14:47:12 INFO     OpenDTU: Inverter "hm800-office": setting new limit from 800 Watt to 184 Watt

2024-09-03 14:47:15 INFO     OpenDTU: Inverter "hm800-office": Limit acknowledged

2024-09-03 14:47:15 INFO     OpenDTU: Inverter "hm700-shed": setting new limit from 700 Watt to 161 Watt

2024-09-03 14:47:18 INFO     OpenDTU: Inverter "hm700-shed": Limit acknowledged

2024-09-03 14:47:18 INFO     OpenDTU: Inverter "hm350-office" reachable: True

2024-09-03 14:47:18 INFO     OpenDTU: Inverter "hm800-office" reachable: True

2024-09-03 14:47:18 INFO     OpenDTU: Inverter "hm700-shed" reachable: True

2024-09-03 14:47:18 INFO     powermeter ShellyEM: 7 Watt

2024-09-03 14:47:18 INFO     setting new limit to 1850 Watt

2024-09-03 14:47:18 INFO     OpenDTU: Inverter "hm350-office": setting new limit from 80 Watt to 350 Watt

2024-09-03 14:47:21 INFO     OpenDTU: Inverter "hm350-office": Limit acknowledged

2024-09-03 14:47:21 INFO     OpenDTU: Inverter "hm800-office": setting new limit from 184 Watt to 800 Watt

2024-09-03 14:47:23 INFO     OpenDTU: Inverter "hm800-office": Limit acknowledged

2024-09-03 14:47:23 INFO     OpenDTU: Inverter "hm700-shed": setting new limit from 161 Watt to 700 Watt

I'll continue to play.

Jonathan

Just make sure it isn't storing the export limit in some sort of EEPROM which has a limit number of writes...

10-10-20

Yes, I was thinking about that yesterday and I know it's using REST to modify the inverter values through the DTU, but then the DTU sends the value as a non-persistant value. I'd be hoping that's in-memory.