Meet the emonTx

At OpenEnergyMonitor labs we have been working on designing a unit that makes building an open-source energy monitor easier. We wanted a unit that is cheap enough for a small home monitoring system yet powerful enough for a large system. We also wanted it to be easy to install and small enough to look pretty!

Two months ago Trystan announced a software milestone with the release of emoncms. Today marks another milestone for us, a hardware milestone with the release of emonTx.

emonTx stands for Energy-Monitoring-Transmitter. It's a small wireless energy monitoring node designed to take inputs from multiple CT sensors, optically from a pulse-output utility meter and from multiple one-wire temperature sensors. It is designed to be powered by 2x AA batteries or 5V USB.

  • Electricity consumption monitoring  
  • Renewable generation monitoring 
  • Heatpump monitoring 
  • Water and gas monitoring (from pulse output meter) 
  • Temperature monitoring 
  • Large scale monitoring - up to 26 emonTxs can potentially transmit to a single base station

emonTx PCB with bare minimum of components
for single channel CT monitoring

The unit has been designed to fit nicely in a case

Sneak peak inside 

emonTx is based on the Atmega328 and is fully compatible with Arduino IDE.   
The design is based on the JeeNodeV5 design, is fully open-source and is designed for easy expandability and compatability with JeeLabs shields.
The firmware is still in development, so far we have an emonTx monitoring a single CT channel and transmitting the data to a base station (Nanode + RFM12 breakout) where it is posted online to emoncms. We hope to release a beta version of the firmware in the next few weeks. 
For more information see the emonTx documentation page

Snowdonia build April 2011

Now that the dust has settled, kitchen cleaned and toilet fixed it seems like a good time to look back on the last week.

Firstly, thanks to Ken Boak, Samuel Carlisle and Matthew Gaffen for making the trip up here to OpenEnergyMonitor HQ in North Wales for the 2nd ever Snowdonia build event. We had a great time and look forward to a reciprocal event in London.

The Team (minus Ken behind the camera)

The idea behind these build sessions is to get together a group of similar minded 'techies' together for a week, add in beer, food and plenty of enthusiasm and have some fun developing cool open-source technology.
Morning planning meeting in the sun

The common theme of last weeks development was sustainability and how open-source technology can be used to help people learn about and reduce their energy consumption and move to energy generation.

The Lab 2010  
The Lab 2011
A rough wiki page has been made here to try and document the weeks developments.

Ken's great blog posts detail day by day developments: 
Mats blog post: snowdonbuild

An interesting development for us at OpenEnergymonitor was Sam giving us a tutorial of how to use Github to share and keep track of open-source code. Over the coming months we hope to shift more of our code to the site. Click here to access the Github group. At present emoncms is the only fully implemented code on Github. 

Snowdonia build 2

6 days of open source sustainable technology development in the mountains of North Wales is under way!

We have Ken Boak, Sam Carlisle and Matt Gaffen all the way up from London hackspace. Suneil Tagore from Machynlleth and Glyn Hudson and myself from here.. Our plans are to work on OpenEnergyMonitor + Nanode applications, we will be updating via the wiki page here over the coming days.

Onawi - Open renewables

Things are really moving fast in the open-source hardware world, and not just electronic hardware. What about an open-source wind turbine design?

Last week Trystan, Suniel and I met up with the team behind OWAWI Open Renewables. They are currently in the process of releasing open-source designs for medium size wind turbines.

This is a very exciting development in the world of open-source hardware. It has the potential to reduce the barriers to entry for wind turbine development, construction and maintenance all over the world.

Should we change to drupal based forums?

Do you think it would be better to use forums integrated into the main openenergymonitor drupal based website? 

This would mean the need for only one login to both comment on specific pages and use the forums. There has also been some extensive spam problems on the current forums which no doubt could be fixed but it could be easier just to use the drupal based forums..

I have set up a drupal based forum in the main site here:

Shall we try it?

Ken Boak's Nanode project

Our friend Ken Boak has been working on an exciting project called Nanode: 

a £20 Network Applications Node for remote sensing projects.

It is an arduino + ethernet + more board. At £20 it will really make a lot of difference to the affordability of networked sensing including very much home energy monitoring. Glyn is working on a battery powered energy monitoring transmitter module at the moment and if we then use the nanode as a base unit adding a small transceiver shield, we should have a very affordable internet enabled home energy monitor.

Check out Ken's blog posts about the Nanode here:

Nanode - It's a bit small isnt it
Nanode - Just make it
Applications for the Nanode

And the wiki space on the London hackspace wiki:

Nanode wiki

Ken is sending a couple of kits up this way soon and we are really looking forward to trying it out! I think there will also be Nanode kits available from Ken to buy in the not so distant future so watch this space!

Andrew Lindsay Ethernet Library
Using the updated ethernet library by Andrew Lindsay you can use this board as a server, a client and can even do DNS queries, check out Andrew Lindsay's work here:
Updated Arduino ENC28J60 Ethernet library available

The free charge controller project

Another awesome project, a project to build an open source charge controller! it looks like a really neat bit of kit!

"The goal of this project is to design a charge controller with maximum power point tracking (MPPT). Maximum power point tracking allows a solar panel, wind turbine, etc to achieve maximum efficiency and deliver maximum power to a load. In this case, a load can be a battery, inverter, or the grid."

Cool projects: Humblefacture

A really cool talk by Dominic Muren of Humblefactory about manufacturing and design:
"Modern manufacturing produces wondrous objects, in massive quantity, at a low price. But the costs to the environment, social stability, and economic justice are large, and often hidden. Small-scale, localized, clever manufacturing would minimize the ability for this cost hiding to continue. More importantly, local production gives the customer a bigger voice to dictate what they need and want out of products."

Dominic has a lot of interesting articles and analysis on his website humblefacture, very much worth a read:

The importance of {human} scale
DJs, Cloud Manufacturing, and the Need for Modular Open Hardware

Emoncms alpha is up!!

As I mentioned in the last post Carlos, Suneil and I have been working on an energy visualisation web application, its a project that's been in development slowly for about half a year now but has only really started to take shape with quite a bit of work in the last month.

Today is a milestone because its got to a point where it is hopefully functional enough to be useful and so here it is a very much alpha release.

The name is emoncms for energy monitoring content management system. And the aim of the project is to develop an open source energy monitoring web app to make it easier to:

1) Understand our whole energy picture ( see screen below )

2) Understand the energy choices that we have

3) Keep track of our energy use and generation over time

Main features

  • Open-source, downloadable, customisable, deployable on any server in the same way as platforms such as drupal and wordpress etc are.
  • Build a whole energy picture by a mixture of manual entry categories and automatic monitoring categories. The whole energy picture intends to follow the approach of
     David MacKay's book Sustainable Energy - without the hot air: linking through to the book and using primarily the kwh/d unit. It also takes a lot of inspiration from Saul Griffiths wattzon in terms of quite a few of the core features.
  • Energy categories are modules (in a similar way to drupal modules) making the application quite extendible, if there's an energy category that you'd like that is not available then you can develop and add it.
  • Renewable energy options suggestions, this could be really interesting, imagine every single type of renewable and efficiency option being related to energy use categories making it possible to quickly get a rough idea for better heating methods, energy saving by switching to an electric car and so on.
  • Connect up to energy monitoring equipment: Extensive and powerful data storage, processing, visualisation, sharing system for energy monitoring data (or any sensor data) from hardware energy monitoring systems. (see kwhd graph screen below)
    Input processing: scale, offset, multiply with another input, log to feed, log to kwhd feed

You can download the alpha version and read more about it on the main emoncms development page here: emoncms dev

The current version is very much work in progress. There is very little error checking, input checking, security implemented. This is all to come. If you have expertise in these areas or would like to get involved in development of other parts of this you would be most welcome, just get in contact via comments on the emoncms dev page or via the forum.

Thanks a lot!

Sustainable Energy and OpenEnergyMonitor development

I really first got interested in sustainability in 2005, I got involved with a group called the welsh youth forum on sustainable development and our main project at the time was on climate change. I remember one meeting where we where discussing what we would do. I remember thinking and suggesting back then that as sustainability requires a shift from our current carbon based use of energy over to renewable energy that a suitable project would be to measure our current use of energy as a group and see if we could make measurable progress towards both reduced use of energy and increased renewable energy.

Nothing came of the idea at that time as I didn't put the work in to make it happen, never-the-less the idea stayed in my mind and the idea of measuring energy so that we can receive feedback on our progress and make sure our actions are effective ultimately let to the starting of this project 4 years later. I also fancied the challenge of building the tools to do this myself as that would allow me to get at and use the data to make the analyses I wanted which was not possible with the household energy monitors available at the time. And it goes without saying that I also think that making these tools open-source would be awesome as open source is awesome.

While learning more about sustainability Suneil, Glyn and I came across a book called Sustainable Energy - without the hot air by David MacKay of Cambridge University: which is a really enlightening book that we got excited about here. The book highlights an approach using quite straight forward maths for quantifying our use of energy in full and then calculating how much renewables we would require to provide that energy.

The result of the calculations is staggering in terms of the scale of the renewables required to provide our current energy consumption: We need country sized areas devoted to renewables to provide significant slices of our energy use. The main message of the book is that we need energy plans that add-up, we cant be anti wind, hydro, solar, nuclear etc etc and not in my back yard and at the same time expect enough energy to do everything we do at the moment and have a healthy biosphere.

Saul Griffiths great talk on energy comes to the same conclusions using much of the same approach, using Watts instead of kWh/d and applied to the world instead of the uk.

So where do we go from here?

I like the way Saul Griffiths puts it very clearly at the start of his talk:

“We've heard about climate change, energy plans... What you probably want to know is how do you fit in, how do you relate to energy. What you also really need are the right tools for making the right consumer choices so that your life can match with the outcome for the planet that you would like.”

Energy monitoring hardware is one part of the tool-set required and we have made good progress with this project on these: We now have an energy monitor for monitoring mains AC electricity use , a multiple input pulse counter to interface with many smart meters a DC energy monitor for microrenewables and a Solar hot water controller/monitor.

The other part to the tool-set is good visualisation of the monitored data so that it can be understood and related to our actions and aims. This can be divided into two parts: standalone displays and computer based visualisations. Glyn is currently working on a stand-alone energy display design and I'm working with Carlos and Suneil on a energy visualisation web application.

We hope the OpenEnergyMonitor tools can complement and build upon the work of David MacKay and Saul Griffiths making it easier to understand our energy use, understand the energy choices that we have and allow us to see and track the progress that we make.

In the next couple of posts I will introduce the energy visualisation web application that we are working on and also three initiative that are in the pipeline that make use of these tools: the CAT microgrid display project, the EcoBro community energy decent project and Megni an energy monitoring and energy visualisation business that Glyn and I have been working on setting up. There has been quite a bit going on recently I feel its time I sat down to update about it.