OpenEnergyMonitor Histogram functionality

A histogram shows the energy (watt hours) by power (watts) which allows analysis of what types of devices (low / medium / high) are using the most energy.

Personal experiences of saving 42% on my electricity use

I have owned an energy monitor for 3 years and using the data downloaded to my PC, can provide good evidence for my significant energy savings:

• 2008 - Got my energy monitor (DIY Kyoto Wattson)
• 2009 - Changed behaviours (like turning off lights) saved 2 kWh per day
• 2010 - A new A++ Fridge saved a significant 1.4 kWh per day.
• The Panasonic fridge freezer has vacuum insulated panels rather than solid insulation.
• 2011 - Replaced most Halogen bulbs with LEDs saved another 1.3kWh per day.
• We are starting a "Halogen Busters" campaign through Transition Towns in North London.

This has resulted in total savings of 4.8 kWh/day which is 58% of the original amount and results in savings of £245 per year.

This histogram chart below shows the distribution of power use. By replacing appliances with more efficient ones, the peaks move to the left (less instant power) and reduce in height (less overall energy). The cumulative lines show the overall savings.

This histogram chart type is going to be incorporated into the OpenEnergyMonitor emoncms by Trystan Lea.

Weather station sending data to Pachube via Arduino

Using Practical Arduino's code to decode the data from a Technoline WS2350 weather station.
Then extended to send weather data and internal temperature (using one-wire DS18B20) to Pachube.
Note the Hope 434 MHz AM receivers are currently in short supply (try www.futurlec.com).

Multi-line charts using dHunter's Pachube Google Visualization API for Pachube app:

Energy Efficiency Leaflet

With increasing energy bills, global warming and peak oil (more expensive, dirtier oil) there has never been a better time to reduce your energy use and invest in renewable generation. Things you can do and useful web sites.
Link to full Leaflet

Things that you can do

1.       Read your meters regularly
This helps you to understand your energy use and provides feedback that any changes are having an effect.

a.       Use a whole house electricity monitor – available cheaply from your energy supplier.

b.      Use a plug-in monitor for individual appliances.

2.       Change your behaviour

a.       Turn lights off when not required.

b.       Look out for stand-by guzzlers
(note, some modern devices have very low standby use).

3.       Change to new appliances

a.       “Halogen Busting” LED lights – the new 6W LEDs give the same quality of light as 50W halogens and are only £11.
That could be a 15% saving on your bill and a 1 year payback.

b.      Replace old appliances with A++ versions .
Your fridge is on all the time and uses a good proportion of your electricity. A new one can have a massive impact.

4.       Renewable power

a.       The “Feed in Tariff” (FIT) provides you with 41.3p per kW hour  generated by solar photovoltaic (PV) panels.
A 3kWh installation will cost about £10,000 and provide about 2400 kWh per year, an average over the year of 6 kWh per day.

b.      Solar Thermal can generate most of your hot water needs.
This can be difficult in our area due to routing pipes to multiple flats.

5.       The “Green Deal” law should be passed in 2012, this will provide a loan tied to the building that will paid using savings from your energy bills.

Websites

·         www.transitionbelsize.org.uk

·         Halogen Busters

o   www.brightlightz.co.uk   for a 5% discount use code “AFD458”
choose 6W warm white bulbs, GU10 or MR16 to suit  your fittings.

·         Electricity Monitors

o   www.diykyoto.com   The Wattson has a bright LED display that makes it easy to change your behaviour,  you can also download the data to your PC.

·         Meter reading

o   Meter Readings for iPhone by Graham Haley

o   www.TheCarbonAccount.com 

·         Solar Panels – local feed in tariff installers
mention “Belsize Energy”

o   www.jojusolar.co.uk

o   www.greentomatoenergy.com

As used at the Transition Belsize Green Fair on 24th September.

GasLog Arduino soure code

Source code for the two parts can be found here:
https://github.com/MarsFlyer/ArduinoEnergyProjects

GasLog an Arduino measuring gas meter pulses

In my home the electricity and gas meters are in different rooms and are difficult to access, so I have taken the approach of using multiple Arduino Pro Minis with cheap RF transmitters and located the main Ethernet Arduino and temperature sensor next to the Internet router.

See here for results from my home: http://www.pachube.com/feeds/19886

I used this low power Hall Effect sensor as it reduced power consumption from 1.5mA to 6µA. Soldering the SMD wasn’t as difficult as I thought. Looking at the battery voltage before the 3.3V booster circuit, it seems that the sleep and interrupt approach seems to be working well for long battery life.  I may also unsolder the power LED as that should reduce the Mini’s consumption from 400µA to 100µA.

Note the hi-tech blu-tack used to hold the Hall sensor to the gas meter – it seems to work well enough. 

Future work will be to add a temperature sensor to the top (and bottom) of the hot water tank. Also add a relay to control a Velux (io-homecontrol) skylight as my home suffers from solar gain on sunny days.

Specific parts:

 #            Mfr. Part #          Customer Part #               Quantity              Price (GBP)         Ext. Price (GBP)

1-            MLX90248ESE                    6              £0.2613                 £1.57

                MLX90248 Series 2.5 to 3.5 V SMT Micropower & Omnipolar Hall Switch - SOT-23-3L

2-            MCP9803-M/MS                              6              £0.8213                 £4.93

                MCP9803 Series MSOP-8 SMD 5.5 V 2-Wire High-Accuracy Temperature Sensor 

http://uk.futureelectronics.com/en/technologies/semiconductors/analog/sensors/magnetic-hall-effect/Pages/3977865-MLX90248ESE.aspx