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You will need the following components:

1. FOR WIRELESS LINKS- (a) Xbee module (for a better quality link but it's expensive) / RF LInk module (Fine Quality but cheap).

2 LED or LCD display.

3.PLX-DAQ software to display data over screen in excel spreadsheet and also show the graphical sketch.

if both water meter and electricity meter have pulse output and you want to do it as cheap you can then 2 emontx modules and 1 emon base can do it. if you want a LCD display  you need a emonGLCD

the electricity meter should have an LED that blinks and for that you can use a photo transistor

for the water meter most of the time it has a magnet inside and for that you can use a hall effect sensor

you can get everything you need in the shop http://shop.openenergymonitor.com/

EDIT: if you have your own server then you can use emoncms to store and display data on a webpage

Thanks for the replies..

What model of Arduino would you recommend using to control the LED strip, store information and make calculations onboard?

Also, does that mean I could set up my own host website using Emoncms and create my own visuals from scratch?

about emoncms... yes... you are free to change the code as you like

i would not store the information on an arduino, but on a database server like the emoncms system

and the emontx is in fact arduino based and the sketch for it are doing calculations

Why would you not store information on the emontx arduino? Can you not just use and SD card or the onboard memory?

Because then I assume you would always require an internet connection, if you stored it on a database server, in order to calculate a new output signal (which is based on stored data) and send the command to the monitor? The idea is that rather than displaying real-time information, the information is a comparison to the average use.

Also, what is the functionality of the EmonBase? Is it possible for the emontx to communicate across a Wi-Fi modem?

Finally, I see that emontx comes with a power adapter, although I've similar systems just use batteries? Is there a significance to this - real power calculation maybe?

I appreciate the help.

Why would you not store information on the emontx arduino? Can you not just use and SD card or the onboard memory?

if using the onboard memory data is lost if the power goes away... you can use the eeprom but after 100000 writes it's going bad, its just the lifetime of eeprom. you can then use an sd card but then the amount of data you can store is limited to the size of the card... text does not take up a lot of space so yes SD card could be an option.

Because then I assume you would always require an internet connection

Yes you would need internet, but who does not have that? But even thou you store data you could display both realtime and compare to old data and even display the average use... the emontx (as it is in the shop) sends the data to the emonbase via FM radio just like most tempsensors etc. the emonbase can handle many emontx nodes. the emonbase are placed next to where your internet connection are. the emonbase then sends the data to the emoncms server. you can run your own server or use the one openenergy provides, up to you. The emonbase are set to upload data every 5-10 secs.. if you run your own server you can lower it if you want to.

Finally, I see that emontx comes with a power adapter... for power you are free to use either the power adapter or battery's. for real power calculations you would also need the 9V AC adapter.

Yeah okay I see. Alternatively though, is it possible to program the SD card or EEPROM to wipe old data after a certain calculation or period of time so as to make space for new data?

Also, I'm just wondering what is the range of the Emontx if it's using FM radio, because this unit may need to be placed outside for monitoring the water meter?

When you say internet, does a computer need to be turned on for this to work?

is it possible to program the SD card or EEPROM to wipe old data after a certain calculation or period of time 

of course... you just write code for the arduino that checks the date on the data and have it delete data that is to old... or a pushbutton that clears everything... loads of options

Also, I'm just wondering what is the range of the Emontx if it's using FM radio

It depends... if there is free air i would say at least 50 Meters if not close to 70... if the wall are made of concrete i would guess for 30 meters if the emonbase is placed in the window

wood is not as bad as concrete but it will block also. the water in the wood even thou maybe only less than 10% is what blocks the signal. a guess in a wodden house would be about about 40 meters.

When you say internet, does a computer need to be turned on for this to work?

no, not if you use the emoncms that openenergy offers... only your modem/router needs to be on.

Many thanks for the quick responses, this is great help. Sorry for all the questions.

Just to be clear though, if you say that I can erase data, can the eamontx read data to make those new calculations. For example, compare the number of pulse inputs taken from 6am (starting time) to 10am with the average number of pulses usually taken within this period - and output a command to the monitor.

I guess the Eamontx uses the cheaper RF Link module rather than the more expensive Xbee module, would this module range much further do you know or would it be worth the investment? Although this would involve me having to make my own circuit from scratch I suppose.

On another note, I've read about the problems of hacking the radio frequency signals on smart meters. I can imagine that the advantages of this wireless communication is susceptible to hacking too?! - there isn't any way around it is there?

I know the guys on this website use a CT sensor for measuring electricity usage but what I have been struggling to find is whether or not attaching a sensor directly on a meter is considering as "tampering" with government property. Do you know anything about this.

Does the Openenergy monitor shop sell hall effect sensors because I cannot seem to find them. I would like to ensure that it is compatible with the eamontx.

I know the guys on this website use a CT sensor for measuring electricity

The CT sensor is clipped arround the wires coming from the meter in to the house, its perfect ok to do this as you dont break any seals. I live in denmark and here we have true 3 phase power everywhere so i would need 3 ct sensors clipped arround each of the 3 wires coming out of the earth-leakage relay (failsafe device that prevent elektro shock). and to be super precise i will also install 3 9V AC adapters. one on each phase.

Does the Openenergy monitor shop sell hall effect sensors

yep they sell both hall effect and CT sensors. http://shop.openenergymonitor.com/components/

On another note, I've read about the problems of hacking the radio frequency

well nothing is completely safe, but for what we use radio for i would say.. let them hack it, for 1 thing they will figure what the heck is beeing transmitted, for a single water meter its just a number. next they will have to be there at time things are transmitted. and even then they will have to filter through everything to get to your transmission. a lot of small things share the same frequence... the transmitter just listens when its ok to send, then it send the groupid, the node id and data, the emonbase then listen for the group id.. everything else is thrown away. with that kind of setup you can have many nodes and so can the people next to you.. they will just have to use another group id. but chances are slim that people with the same system within 100 meters use the same setup as you. if you get false but steady data just change group id and you should be fine.

I guess the Eamontx uses the cheaper RF Link module rather 

it does have better range yes... and its 2 way able... what you should ask yourself are if you relly need it. how far from nearest window are the water meter? you can partly test the range but setting a wifi spot in the window and see if there is wifi at the water meter...

Just to be clear though, if you say that I can erase data

Of course you can only make calcs on the data you have.. so you need to decide how old data you want to keep and then make the code either delete data automatic or when you press a button.. you could make 1 button that deletes everything and one that deletes but holds data for the last week. but again i would be lazy and use emoncms as that holds data much longer back and have lot of options for making graphs etc

I think most domestic electricity monitors in Ireland are single phase so perhaps I just require 1 CT sensor. Modern ones have a flashing LED which would require the optical sensor.

yep they sell both hall effect and CT sensors. http://shop.openenergymonitor.com/components/

Is it the temperature sensor?? This is the same page I was on before I asked you but they're not called hall effort sensors anyway...

Of course you can only make calcs on the data you have.. so you need to decide how old data you want to keep and then make the code either delete data automatic or when you press a button.. you could make 1 button that deletes everything and one that deletes but holds data for the last week. but again i would be lazy and use emoncms as that holds data much longer back and have lot of options for making graphs etc

Sorry, no I understand that you can erase data, but the eamontx can carry out a series of onboard calculations between new and previously stored data based on time and amount of pulses to calculate an average use, and then send the result to the display monitor, am I right in saying that?

However maybe I will just leave it down to the Emonbase and cms to store all the data  and carry out all the calculations. Do you have any recommendations for which EmonBase  to get?

upps about the hall effect.... you can get one here: http://uk.rs-online.com/web/p/hall-effect-sensor-ics/3683945/

yep, if you keep the data you can do calculations...

for emonbase either this one: http://shop.openenergymonitor.com/nanoderf-smt-868mhz-europe-only-pre-as...

or

http://openenergymonitor.blogspot.co.uk/2012/11/raspberry-pi-emonbase.html