Apps

Apps are ready-made dashboards for common applications. Each app needs a small number of feeds and does its own calculations, such as daily totals, self-consumption and COP.

The two main apps are My Electric Flow for electricity use, solar and batteries, and My Heatpump for heat pump performance.

Add an app

1. Click Apps > New in the menu to open the Available Apps page.

2. Click an app. Featured apps are listed first.

3. Enter a name and click Create.

4. The app opens on its configuration page. Feeds with the default names are selected for you. Select any feeds that are not found and click Launch app.

To change the configuration later, click the spanner icon in the app.

Tip

Use the default feed names when you set up input processing, for example use, solar and heatpump_elec. Apps then find the feeds without manual selection.

My Electric Flow

My Electric Flow shows how electricity moves between solar, battery, grid and home. It covers what the archived My Electric, My Solar and My Solar Battery apps did.

It shows:

• Live power for use, grid, solar and battery, with battery state of charge and time left.

• A power graph and a daily kWh bar graph.

• An energy flow breakdown for the selected period: solar to home, solar to grid, solar to battery, battery to home, grid to battery and grid to home. Self-consumption and self-sufficiency are shown as percentages.

• A Tariff explorer that costs each flow on a chosen tariff, including Octopus Agile and other UK time of use tariffs.

Feeds

Tick Has solar PV and Has battery to match your system. Then select the power feeds in watts.

Setting	Default name	Description
use	use	House or building use
solar	solar	Solar generation
battery	battery_power	Battery power, positive for discharge and negative for charge
grid	grid	Grid power, positive for import and negative for export
battery_soc	battery_soc	Battery state of charge in %, optional

The app calculates one missing feed from the others. You need:

System	Minimum feeds
Solar and battery	3 of use, solar, battery, grid
Solar only	2 of use, solar, grid
Battery only	2 of use, battery, grid
Consumption only	use or grid

Flow history

The daily view and the tariff explorer use cumulative kWh feeds for each energy flow, for example solar_to_load_kwh. The app creates these feeds and fills them from your power feeds with the solarbatterykwh post processor. The app updates them each time it opens. The feeds are created under the node solar_battery_kwh_flows.

The post process module must be installed. It is included on the emonPi and emonBase.

Other options

• Show kW: show power in kW in place of W.

• Battery Capacity: capacity in kWh, used for the time left estimate.

• Flow allocation strategy: Solar first or Battery first. Sets which source supplies the home when both are available.

• Tariff: region and tariff for the tariff explorer.

My Heatpump

My Heatpump shows heat pump performance: electricity input, heat output and COP. It is used by many of the systems on HeatpumpMonitor.org.

It shows:

• A daily bar graph of electricity input, heat output and COP. Click a day to open the power view for that day.

• A power view with flow, return, outside and room temperatures, flow rate and instantaneous COP.

• COP and SCOP for the full window, when running, space heating, water heating and cooling.

• Chart options: immersion, flow rate, hot water temperature, defrosts, simulated Carnot heat output, emitter and system volume calculation.

Feeds

Only heatpump_elec and heatpump_elec_kwh are required. Add a heat meter to get heat output and COP.

Setting	Description
heatpump_elec	Electricity input in watts
heatpump_elec_kwh	Cumulative electricity input in kWh
heatpump_heat	Heat output in watts
heatpump_heat_kwh	Cumulative heat output in kWh
heatpump_flowT	Flow temperature
heatpump_returnT	Return temperature
heatpump_outsideT	Outside temperature
heatpump_roomT	Room temperature
heatpump_targetT	Target room or flow temperature
heatpump_flowrate	Flow rate
heatpump_dhw	Hot water circuit status, non-zero when running
heatpump_ch	Central heating circuit status, non-zero when running
heatpump_cooling	Cooling status, 1 when cooling
heatpump_dhwT	Hot water temperature
heatpump_dhwTargetT	Hot water target temperature
immersion_elec	Immersion heater electricity in watts
boiler_heat	Boiler heat output in watts, for hybrid systems

Other options

• Starting power: power in watts above which the heat pump counts as running. Default 150 W.

• Enable daily pre-processor: splits daily totals into space heating and water heating.

• Auto detect cooling: detects cooling when no cooling status feed is set.

• Start date: ignore data before this date in all time totals.

See Heat pump monitoring for hardware and feed setup.

Other apps

App	Use
My Boiler	Boiler fuel input, heat output and efficiency
My Solar Divert	Solar generation, household use and PV diversion
Time of use - flexible	Costs on multiple time of use tariffs
Profile	Average daily profiles for each month
UK Grid	UK grid fuel mix and wind and solar forecast
CO2 Monitor	Room air change rate from CO2 decay
Psychrometric Chart	Indoor temperature and humidity against comfort zones

Older apps are listed under Archived apps on the Available Apps page. They still work but are no longer developed.

Source code

The app module is on GitHub: emoncms/app.