OpenEnergyMonitor

The current front page

It has been pointed out several times that the documentation on this site is hard to follow. We've been giving this some thought and have come up with a plan for hopefully what will be a clearer structure.

Here are our initial thoughts:

1) We start with the following headings, these form the main menu:

Community | Applications | Modules | Fundamentals | Tools | Archive

These headings contain:

Community

• Forums
• Development plans
• Links to community builds and blogs

Applications
Applications are step by step guides of how to assemble modules to create a particular system. They start with a short description then a step-by-step type structure. Detailed application discussion would be on a second page or blog post with link through.

• Power monitoring
• Solar PV
• Solar hot water
• Pulse counting
• Heatpump monitoring

Applications reference through to modules below.
Separate github folder for each application containing sketches for all the modules that make up the application.

Modules

• Hardware
• emontx
• emonglcd
• emonbase
• See-a-watt
• Software
• emoncms
• Pachube

Each module contains the pages:

• page1: overview + features (maybe use it: application list is referenced here?)
• page2: built it / install it / buy it
• page3: detailed design documentation

All emon system sections reference through to fundamentals section below

Fundamentals

Getting started with arduino, uploading sketches etc.

Electricity monitoring

• AC Theory - Introduction
• AC Theory - Advanced
• AC Theory - 3 phase
• Power in different countries

• Non-invasive
• CT sensors - Introduction
• CT sensors - Advanced
• Current only - Single Phase
• Current and voltage - Single Phase
• 3-phase Monitoring
• Invasive
• AC shunt
• DC Shunt & hall effect sensing

• Appliance inference - labs
• Interfacing with inverters

Pulse counting

• Single pulse counting
• 12 input pulse counting

Temperature

• DS18B20 temperature sensing
• PT1000 temperature sensing

Networking

• RF
• RFM12B
• xbee, zigbee, old rf
• Master/slave simple serial networking
• Ethernet

Displays

• GLCD
• 7segment, 3310

Storage

• USB Pen drive data-logging
• SD Card logging

Control

• Relay

Firmware

• Watchdog timer
• Structures for transmitting data.
• Sleep mode
• String constructor

Github sketches for the fundamentals section could be contained in one github folder called fundamentals.

Tools
Tools that can be useful in debugging / development of systems:

• VI Sampler
• KST based graphing and statistics
• Programming nanode with arduino

Archive
Items for archive

Other changes
We've disabled comments on pages, the thinking here is that its getting quite hard to navigate the page comments as conversations at different dates and topics are all getting mixed together and that it would be better to have these discussions on the forum, where each forum thread has its own clear topic.

Every page can be put in a hierarchical order such as modules/hardware/emontx making navigation clearer.

A site map with all of the above.

Do you think this is a good idea? 
Any suggestions on how the website content can be better arranged would be greatly welcomed!
Thankyou!

Its good to know as soon as possible if there is an issue with an installed energy monitor, such as the base station dropping offline or a problem with RF connection. This is a rough and ready first implementation of an email notifier for emoncms, that sends you an email to say that a feed has become inactive or a feed is equal to a certain value. No longer are the days when you log in to emoncms just to find that there are two days of missing data as happened to me on feb 6-7 here
A walkthrough
1) Click on a feed in the feed list to bring up the feed view page, scroll down to the bottom and click on set notifications:

2) Select the events that you want notifications for. Notification on value and on inactive both work. Periodic notification is yet to be implemented.



















3) Click on edit mail settings and enter in the recipient email address. This only has to be done once as it is the same for all notifications.














If you want to send the notifications to multiple addresses, just put in a comma between each address.

4) Unplug your emonbase!! and check your email:












It can be tried out here: http://vis.openenergymonitor.org/emoncms3

Behind the scenes


Main scripts:

notify_model.php
mail_model.php
notify_controller.php
notify_view.php



Installation/Setup
1) To use the notifier on your own server you will need php mail installed, to do this on ubuntu enter the following into terminal

sudo apt-get install php-pear
sudo pear install mail
sudo pear install Net_SMTP
sudo pear install Auth_SASL
sudo pear install mail_mime


2) In emoncms3/Includes copy the default.mail_settings.php file and rename too mail_settings.php and enter in your mail server settings.

3) Open the file cron.php and change the key password to something unique, this is used to ensure that only you can run the cron.php script.

4) Create a cronjob, in ubuntu start by opening crontab: $ crontab -e
Then add a cronjob that calls the cron.php script including the key that you created. To call the cron.php script once a minute try the following:


# m h  dom mon dow   command
* * * * * wget -q -O /dev/null "http://localhost/emoncms3/cron.php?key=YOURKEY


5) If your using the same database as a previous emoncms version, you will need to create the new notify database tables. This can be done in index.php by pasting require "Includes/setup.php"; in the top. Its probably worth removing it afterwards.

6) Configure your feeds as in the screens above!

Spent a bit of time implementing new features for emoncms today, the first one was a much needed but quite small addition: a themed location to output messages such as "user already exists" and so on, see the blue bar in the screen below:



Try it out here: http://vis.openenergymonitor.org/emoncms3/

How it works

If you have a look at the user_controller here github user_controller.php
On line 28 and 29 you will see the following:

$output['content'] = "";
$output['message'] = "";
(ie line 65) $output['message'] = "Your new account has been created";

The returned output from the controllers used to be just the one variable $output now we have two, one for main body content output and the other for message bar output. These variables are passed through index.php to the theme The theme then places the message and content in separately themed locations.

If you are an active member of OpenEnergyMonitor.org, then you know for sure that one of the challenges the project is facing is monitoring tri-phase AC systems (220V-400V).
In theory it is as simple and easy as monitoring three one-phase systems with one voltage sensor per voltage phase, but in real life, it is not as easy as that.Most of the time, plugs of the different phases are far from each others, and often there are no plugs for one or more phases (if it's for a special purpose like a night water heater). So this implies cabling one plug for each of the three phases in the cabinet and using 3 voltage sensors.
This would hit one of the most important features of OpenEnergyMonitor: non-invasiveness. It would imply significantly more cabling and electrical work, this would also mean higher costs.
I happen to know enough about principles of electrical power to be convinced that we can use one voltage sensor and three current sensors to monitor three-phases systems. Here is the theory:Source: http://www.electronics-tutorials.ws/The three voltage vectors are always shifted by 120°. What changes is the angle between a certain phase voltage and current vectors (a change caused by the properties of your load, but that's another story). So if the angle between two voltage vectors is always the same, then the phase shift of a current vector to the another phase voltage vector is exactly the phase shift of that current vector to its voltage vector + 120°.
Example from the figure above:Phaseshift of red phase current and voltage= Phaseshift of red current vector and yellow voltage vector.
So if we calculate the power factor of a current with any other voltage, we will of course get a wrong one, but we can always shift it by 120° and get the right one.
I have a setup of what I call "See-a-Watt" (which is basically a device based on the plans and code of OpenEnergyMonitor, but that combines data acquisition ethernet connection) installed in a building on the campus of my university, with access to a three-phases installation. So I decided to test the theory there.
The approach is as follows:

1. Sample one voltage waveform out of three
2. Sample three current waveforms (of each phase
3. Calculate the phase shift (aka. power factor) of each of the three current waveforms to the one voltage waveform.
4. Send Vrms1, I1,I2, I3 and the power factors relative to each phase to emonCMS
5. Reverse the power factors to get the "wrong" phase, then compensate it with 120° and recalculate the "right" power factor
6. Calculate the "right" powers = Ix * Vrms1 *'correct PF'

With the help of Trystan (he's much better with PHP than me and he knows emonCMS like the back of his hand) we implemented a function in emonCMS that reverses the "wrong" PF to the "wrong" phase shift angle, then shift it by + or - 120° and recalculate the PF.
This setup is working now for more than 6 weeks without any problem and the accuracy is comparable to the traditional accuracy of the non-invasive method: 1-2% not more.
Here is the code on the device side: https://github.com/AminfiBerlin/See-a-Watt-3-Phases
and here is the commit on emonCMS that introduced the phaseshift function: https://github.com/openenergymonitor/emoncms3/commit/a41c57d457df77697540b1a89a74486951e058ee
Needless to say that this is still in beta, I did not have any problem with it so far but that doesn't mean it's perfect. Please feel free to download the code and test it in every possible way.
This is my first real contribution to any OpenSource project at all, I feel so proud and happy to be able to give back as much as I can.
By Amin Zayani

Over the last year Glyn Hudson, Bethan Gritten and I have been running a community energy project with our local sustainability group Ecobro in the Penrhyndeudraeth area of North Wales. The aim of the project is to create a comprehensive snapshot of our current energy use as a group that we can then use as a solid foundation for creating a sustainable energy action plan.
As part of the project we have installed 20 openenergymonitor energy monitors and have also developed for the project a community energy auditing and plan making application which is what this blog post is about.
This is how the application works:
1) Fill out a single household energy audit, compare how your energy picture compares to the average UK household energy use and how it relates to the Centre for Alternative Technology Zero Carbon Britain 2030 energy scenario:

2) Aggregate data from each household to create a group view:

3) Explore how group scenario is built up of individual households contribution:

4) Explore future energy scenarios, see the effect of switching to electric cars, heatpumps etc on real household data from your group:

5) In the next version, see effect of energy efficiency measures, insulation, draft-proofing and see the cost and payback details of scenarios including a comparison of different measures by sustainable energy % increase impact per £.
The idea is that through this process we can help bring focus to areas and solutions that can have most impact and also give a tangible reference of progress so that milestones can be celebrated when achieved.
The application is largely inspired by David Mackay's book Sustainable Energy Without the Hot Air (free to read online) as you can see from the use of the energy stacks. The aim is also very much about creating a tool that helps to create sustainable energy plans that add up and in the spirit of openenergymonitor and David Mackay's book the application is open source.
Download the source from github: https://github.com/openenergymonitor/CommunityEnergyPlanMaker
Try it out:http://vis.openenergymonitor.org/cepm/
If you would like to help with development that would be great, please get in contact / send us github pull requests. If your doing a community energy plan making project and would like to use this tool, please do and let us know how your using it. 

Hello, my name is Baptiste Gaultier. When I started working on the project of monitoring the energy consumption of Telecom Bretagne (an engineering school in Brittany, France), I was looking for products which can measure, store, and track the energy consumption data of a typical university campus.

After spending some time researching the available solutions, I found a lot of expensive proprietary products and a project you may have heard of, called openenergymonitor. This project provides a very powerful, web-connected energy monitoring system, and the best part is that it is open-source !

I started to work on top of emonTx and emoncms and here are some new features I added to emoncms (the new hardware features will be addressed in a future blog post)  :

• Map widget : allows you to see a map with all the sensors used for energy monitoring
• Device manager : provides an easy way to add devices on the map widget
• Node information widget : allows you to see all information (hostname, IP addresses, device type, power measured...) of a monitoring node

Screenshots

Dashboard with my university campus map


Device manager tab

We have made some progress, but we have still a lot of work to do before our goals are met, most notably:

• Tagging and renaming the devices
• Displaying the energy chart when clicking on a node
• Drag and drop node positioning on a map (device manager)
• Node filtering (depending on power consumption for instance)
• How to use the map widget (documentation) 

The code has been released on github (I forked couple of days ago) : https://github.com/bgaultier/emoncms3/tree/devicemanager

The entire team working on the project at Telecom Bretagne is convinced of the great quality of the openenergymonitor project and we hope our work may be useful in any way.

Cheers !

The emonGLCD is an open-hardware wireless graphical LCD display based on the ATmega328 microcontroller and is Arduino compatible.



The emonGLCD works very well as a real-time living room energy monitoring display. For the emonGLCD to calculate and display how much energy has been used on the current day it must know when the day begins and ends. Therefore it must know the current time.

The emonGLCD does not have a hardware RTC but its possible to implement a very accurate clock using the Jeelabs software RTC library and a web-connected Nanode RF. In the OpenEnergyMonitor end-to-end energy monitoring system the emonGLCD is used in conjunction with the emonTx (transmitter) and emonBase/NanodeRF which is used to post data on-line to emoncms.

When data is posted to the emoncms sever with a http request the sever response contains the current time of the sever. We have written a code example to extract this time from the http header reply and pass it via RFM12B wireless to the emonGLCD. The time on the emonGLCD is always correct. Both the emonGLCD and the NanodeRF receive power monitoring data from the emonTx

Demo video (single CT sensor system):



Demo video (solar PV monitor system):



Taking this a step further: when the emonGLCD receives the time from the NanodeRF the emonGLCD transmits back the current room temperature from it's on-board temperature sensor, then the NanodeRF posts this online to emoncms.

The Arduino sketch examples are up on github:

emonBase/NanodeRF:
https://github.com/openenergymonitor/NanodeRF/tree/master/NanodeRF_singleCT_RTCrelay_GLCDtemp

emonGLCD single CT:
https://github.com/openenergymonitor/EmonGLCD/tree/master/emonGLCD_singleCT_AutoTime_TempLog

emonGLCd solar PV: https://github.com/openenergymonitor/EmonGLCD/tree/master/emonGLCD_solarPV_type_1_and_2

The mission of the OpenEnergyMonitor project is to design and build and open-source energy monitoring and eventually control system. We would like this system to be work well for home energy monitoring systems but also be scalable. For more information see our newly updated project vision.
We are now at the stage were we have a fully functional end-to-end web-connected home energy monitoring system. We have recently written a full step-by-step build guide for the system. This build guide covers everything from assembling the electronics, uploading the Arduino firmware to setting the web dashboard. 


The system consists of three wireless hardware units emonTx (transmitter), emonGLCD (display), emonBase (web-connected base station) and a powerful web-application emoncms.
We also have build guide/documentation for setting up a solar PV monitoring system using the same modules. 
We are working towards opening an online shop to sell the hardware units (initially in kit form). Please fill in the interest form if your are interested.