Getting and installing your EMMA

Where can I get an EMMA?

Us! – Give us a call on 01386 871490 or fill in the form here:

What warranty does EMMA come with?

EMMA units come with a comprehensive back to base (Dublin) warranty for 12 months from date of delivery. An extended back to base warranty is available for £50 per additional year.

Do I need to let my DNO know that I am using an EMMA?

You only need to let your DNO know that you are using an EMMA if you are using a GVS model to manage exports to stay within the DNO’s permitted maximum export.

How long does shipping take?

Once your EMMA is in stock, shipping is two days to major areas in Ireland and UK. Any post codes out of the way will take longer to deliver in the UK.

I installed/ordered my generator before I heard about EMMA. How can I get an EMMA with it?

EMMA is easily retro-fitted, so if your installation is imminent you can always go ahead with it and ask your supplier to get in touch with us so they can supply and fit an EMMA for you afterwards. If possible, get your installer to contact us before your generator is installed so our engineers can brief them on preparing the wiring and mounts for EMMA so it is more quickly slotted in afterwards. We recommend that you ask your reseller to place an order for EMMA asap as demand for EMMA is such that we occasionally have a waiting list.

Would one EMMA unit be able to manage the outputs of the two PV systems?


Does EMMA work with thin-film glass modules, solar glazing, cladding etc.?


Can we have a completely mismatched system i.e. with a large array feeding a small EMMA and load? What happens with the excess power that is above that required to feed the load? If it is ok to have a mismatched system, then why do you specify a maximum generator size in the Sizing Guidelines?

Yes, you can have a mismatched system where much more power is produced by the generator than could ever be used by the available loads. However, when ordering EMMA for such a mismatched system you will have to specify the size of the generator to us so that we can specify the CTs – for example, the standard EMMA SP15 comes with a 20 amp CT for the output generation as standard, but this would have to be swapped to suit a larger output. The excess power will be exported. The Sizing Guidelines specify the max size to correlate to the CTs that we supply for our standard EMMA systems. We also specify max array sizes for ideal scenarios. EMMA systems can be customised to suit your needs. Please liaise with your local reseller.

What physical size is EMMA?

The dimensions of each EMMA unit are 375mm wide x 182mm high x 184mm deep.

What size is the box that EMMA is shipped in?

The size of the boxes that EMMA is packed and shipped in are 460mm x 240mm x 280mm.

How much power does EMMA use?

EMMA uses less than 10 watts on standby.

Where should I install it?

In any cool dry place that remains below 30 degrees. Typically beside the heat store or under a fuse board. It is possible to fit EMMA units remotely from the consumer unit using long CT leads. It can be fitted beside the hot water cylinder, for example, providing that you can run the CT leads back to the incoming tails from the grid and the inverter. EMMA would not normally be fitted beside the electricity meter.

How long does EMMA take to install?

The average install takes 4 hours on a retrofit and about 2.5 hours on an installation with the PV/turbine going in at the same time. For electricians who have installed EMMA before it takes less time. The reason for the time difference is the rearranging of the inverter connection through the Henley block for the correct configuration of the CTs.

Can the EMMA work in conjunction with a Vphase voltage regulator?

The V phase only connects certain circuits. EMMA will work with any house that has a V phase but it will be connected outside the V phase circuit so in effect it doesn’t matter whether a house has V phase or not.

Can we install an EMMA system to run alongside an existing voltage optimisation unit? The property is run entirely off electric so we are looking at all ways to reduce their consumption. By dropping the voltage to 220 I assume this doesn’t have any negative impact on the running of the EMMA unit?

The EMMA unit should be outside of the Voltage optimiser unit and be supplied by normal mains similar to the inverters. Using the EMMA on the VO circuit would give a different voltage to that of the voltage from the inverter and hence would distort the power readings.

Can I use EMMA to charge batteries?

In the case of battery charging we would need to determine if the charger will function with PWM controlled input. If it doesn’t we could provide a 0-10V DC control output that can be used to adjust the chargeing rate. This will require a charger that can take a 0-10V DC control input. Contact your Reseller with the details of what you wish to do and as necessary we will assist them with the design of a solution for you.

Pricing, ROI and comparing EMMA to alternatives

How much does EMMA cost?

Give us a call on 01386 871490 or fill in the form here:

What VAT rate will you charge for my EMMA installation?

If EMMA is supplied as part of a solar PV or wind/water turbine system installation, the reduced 5% VAT rate applies. If EMMA is sold as a retro-fit, the standard 20% VAT rate applies. (This applies to UK installations).

What return on investment will I get?

See our Benefits and Return on Investment pages.

What about cheaper devices on the market that claim to do a similar job as EMMA?

Buyers should be wary of other devices on the market that claim to efficiently manage surplus energy from your renewable generator. These products may be relatively cheap to buy, but could cost you dearly in the long run – both in terms of your energy bills and energy usage. The fact that these devices are so inefficient is the very reason why Cool Power Products developed EMMA.

There are no other products available that are as effective as EMMA. EMMA uses new, unique, patented technology that is not available in any other device. The other devices on the market use inferior technology that may actually increase your energy usage and electricity bills. The reasons for this are simple – our blog post explains why: Why EMMA Outshines Other Devices.

What advantages do ‘solar PV with EMMA’ systems have over solar thermal?

It may make more sense for you to install EMMA with solar PV instead of thermal solar because the cost of EMMA is approximately 40% of a thermal solar system and results in greater savings over time. See the FAQ section on Choosing EMMA and Solar PV vs Solar Thermal.

I use gas or oil for my heating and hot water. What return will EMMA give me?

Some customers with oil or gas central heating / hot water systems buy one or more electric storage heaters or electric heated towel rails so they can use with EMMA to reduce how much heating they continue to need from their oil or gas system. It may also be possible to add an electric immersion to your gas/oil fired hot water tank so that EMMA can send power to it – again reducing how much oil or gas you consume for hot water. The savings you make equate to what you save on your oil or gas bills.

When calculating the savings remember that while oil/gas costs around 5p per unit and electricity costs about 15p per unit, the effective price of gas/oil relative to electricity is more than 5p because of the relative inefficiency of using gas or oil. Where electricity is 100% efficient, we estimate that oil and gas are about 50% efficient, even where boilers are said to be 90% efficient. So, when comparing the effective cost of oil/gas to the cost of electricity, you may wish to almost double the quoted unit cost of gas/oil.

Also, gas and oil tend to heat water quickly and to high temperatures – which can lead to lots of churning and heat losses from the tank. Because EMMA heats the water more gently, these heat losses are reduced by up to 50%, saving you money. EMMA also produces savings by giving you better control of hot water temperature. These benefits are described in more detail in the FAQ section on Immersions.

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Using EMMA

What does EMMA stand for?

Energy and Microgenerator MAnager. When EMMA was originally designed it was intended to work with domestic-size microgenerators of around 3kW, hence the name. Since then it has been extended to work with micro, small, medium and large generators – and you can control loads of up to 300 kW.

How does EMMA work, in brief?

EMMA has the unique patented ability to send anything from 0W to 3,000W to a 3kW immersion heater in real time. It is fitted with two CTs (current transducers) that enable it to monitor and compare the output from your renewable generator (e.g. solar PV, wind turbine or water turbine) and the demand of your household (including the demand of your immersion heater) in real time. It uses this information to adjust the amount of power being sent to the immersion heater from 0% to 100%, also in real time. By doing this it ensures that total household demand matches the output from the generator precisely at all times when the generator’s production would otherwise exceed the household demand.

  • When the output from the generator exceeds household demand, EMMA increases the amount of electricity going to the immersion heater. This in effect brings household demand up to match generator output.
  • When household demand exceeds the amount of electricity being produced by the generator, EMMA reduces the amount of electricity being sent to the immersion, and if necessary allows grid electricity to be imported to meet household demand.
  • Example: If your PV system is generating 3kW and your household is consuming 2kW, EMMA will send the remaining 1kW to your immersion heater.

EMMA in effect puts all the surplus generator output into the hot water cylinder (or other heating/cooling loads in the houseshold, as you wish). This is typically 50-70% of the total generator output. During much of the time you are effectively getting free hot water.

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Solar PV with EMMA, or Solar Thermal?

In a typical domestic situation EMMA provides you with the equivalent of adding a solar thermal system at below half the cost – and you utilise most of what you generate. This means your investment in your generator works harder for you. The calculation to compare the two options is relatively straightforward. What counts is:

  • The estimated cumulative output of your solar PV system for the year.
  • How much of that output is put to use by EMMA onsite (directly reducing your energy bills) rather than being exported.
  • How much that will save you on electricity bills and earn you from feed-in tariffs.
  • Compare those savings/income with how much solar thermal saves you by providing you with hot water.

Remember that solar thermal can only supply you with hot water. Therefore, if you spend £300 a year on heating on hot water, you can only ever save £300 a year by having solar thermal.

Solar PV with EMMA, on the other hand, can heat your hot water AND then put any additional electricity generated by the PV to further uses, such as space heating. So, you save that £300 plus the value of any other uses the electricity is put to (general household needs, storage heaters, etc.).

EMMA also gives you finer control of your immersion heater and hot water temperature so you do no overheat water, and there are fewer heat losses due to convection in the immersion (see FAQs). Your hot water is produced more efficiently.

Because solar PV and EMMA do not involve plumbing, you do not suffer any heat losses from the piping between a solar thermal system and your immersion heater, which can be quite substantial.

The other advantage of EMMA is that it is quicker and easier to install than solar thermal because it is simply an electronic device that integrates with your existing wiring and PV system. Installation involves no mess, no plumbing, no disruption and no risk off future water leaks as can happen with solar thermal.

That is not to downplay solar thermal – it has its use and its place. Indeed, in certain situations, people use both solar PV with EMMA, and solar thermal.

There is a graph here (“EMMA SP15 Installed and Saving Money within an Hour”) that may interest you.

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EMMA and your immersion

Do any changes have to be made to my immersion heater or hot water tank or system to use EMMA?

No. If it is a standard immersion it should be fine.

However, larger-scale customers may want to consider investing in an upgraded specification hot water tank or accumulator if they are spending large amounts installing microgenerators for use with EMMA. The upgraded systems can be fitted at the same time as the microgenerator and EMMA or retrofitted at a later date.

Does EMMA give me additional control over my immersion?

Yes. EMMA gives you hot water exactly when you need it, and at the exact temperature you want. In addition to the above functions, EMMA acts as an advanced time and temperature based controller for your hot water cylinder. It will ensure that the hot water reaches your menu-set minimum desired temperature during pre-set time periods (two per day), drawing the minimum amount of power required from the grid to do this on days when there is little or no generator output. The hot water timer allows for two heating periods per day.

If the water is brought up to temperature and surplus electricity is not being used elsewhere in the house (e.g. for underfloor heating, towel rails etc.), only then will electricity be exported.

Hot water boost is on demand. EMMA comes with a boost button that replaces the timer switch often found in houses for switching the immersion heater on/off.

EMMA also has a holiday schedule and maximum safe temperature setting to ensure that the system switched off at the beginning of the holiday and back on at the end and to ensure that the system doesn’t overheat on exceptionally sunny days.

What is the purpose of EMMA’s ‘Holiday mode’?

You can set the EMMA unit to Holiday Mode for specific days you select. This switches off the EMMA and the hot water immersion, so diverting excess electricity to the grid. The logic for this is that there is no point in using excess electricity for heating hot water while you are away. Export tariffs can therefore be exploited effectively.

What performance improvement does the optional temperature sensor give?

The optional temperature sensor that comes with EMMA is more accurate than the sensors (thermostats) that typically come with immersion tanks. This greater accuracy means that the immersion will only heat your water to the temperature you want – it does not overheat it above what you need – so you do not end up using more electricity than you need. This is most important when you are drawing electricity from the mains to supplement your solar/wind electricity, as you don’t want to import more electricity than is necessary for the hot water you need.

Is the temperature sensor that comes with EMMA wireless?

No, the temperature sensor is not wireless. You need to wire it to the EMMA unit. The temperature sensor supplied with the EMMA unit normally slots into a probe pocket on the hotwater tank or else is stuffed inside the insulation layer against the copper of the tank, about two-thirds of the way up the tank. You will require CY-OZ 2 core .75mm shielded cable for connecting the temperature sensor to the EMMA. You will also require a run of this cable to each of the CT’s and to the Boost button.

Where in the hot water tank should I position the immersion?

The immersion is normally in the bottom third of the standard tank or else it will come in at the top and goes down into the tank. Either is normal. The hot water will rise to the top of the tank in any event but it is preferable to have the immersion at the bottom so EMMA can heat more water.

If the EMMA switches on our immersion heater when there is only a small excess of PV electricity, is there a risk that the 3kW immersion heater will also then draw additional electrical power from the mains, for which I will have to pay full price?

No, it will not draw additional power from the grid. This is a problem with inferior devices on the market. EMMA, however, is specifically designed to avoid this using patented technology. For more info read our blog post Why EMMA Outshines Other Devices

I don’t want any power going to the water tank except for frost protection. Can I do this?

Yes. You can set the max safe temperature to 5 degrees to achieve this. You will need your EMMA unit to switch over to a secondary load when the tank temperature reaches 5 degrees… and vice-versa. Depending on the version of EMMA you have, it may be possible to reduce the minimum setting for the minimum desired temperature to 3 degrees. If you set this to 3 degrees and set the schedule to 24/7 you will get the frost protection you are looking for.

What if my immersion is 3kW but my generator is only producing 2kW? Will an EMMA send just 2kw to my immersion heater when PVs are only generating 2kw even though my immersion heater is 3kw, or does EMMA wait until at least 3kw is being generated by PVs before sending power to my immersion?

EMMA will match any excess power from your PV array above your household demand and send it to your immersion. EMMA can vary the power from 0 to 3kW. It can send 2kW to a 3kW immersion as you have indicated. It will not wait for 3kW to be produced before switching on, If there is 10watts available above what you are using in your house then 10 watts will be sent to the 3kW immersion. The immersion will still work fine.

You mention that EMMA also results in savings because of reduced heat losses from the immersion?

Yes. One of the unexpected benefits from using EMMA is significantly reduced heat losses from the hot water cylinder. This is the result of EMMA ‘trickle charging’ the hot water cylinder for most of the time (i.e. operating the immersion heater at low outputs) and thereby preventing wasteful convection driven ‘churning’ that occurs when the immersion heater is operated at full power. We have observed this reducing losses from hot water cylinders by up to 50%.

Does the immersion heater need to be on constantly if it is to be controlled by EMMA?

Yes. EMMA will turn it on and off then depending on the available electricity and your heating requirements.

Is it possible to run my immersion only when surplus electricity is available, and program it so that it never uses grid electricity for hot water?

Yes. EMMA allows you to set times when you want definitely want the hot water to be at or above a minimum desired temperature. These times are typically at 7.00 am to 8.00 am and 5.30 pm to 9.30 pm. EMMA then ensures that the hot water is brought up to this temperature for these time periods – with the help of mains electricity if necessary.

If you never want to use mains electricity for hot water, you just set these heating periods to run from 7am to 7am and 6pm to 6pm or equivalent. In other words, you are setting the defined hot water heating periods to zero. EMMA will now heat the water towards a target temperature when surplus electricity is available, but will never draw grid electricity to heat it. These settings can be changed at any time.

What would happen if EMMA’s heat sensor failed – would EMMA continue to send excess power to the immersion and if so would the tank start boiling or is there a fail safe device to prevent this?

The existing immersion heater thermostat(s) act as the fail-safe safety device in the event of the EMMA sensor failing. The EMMA sensors are solid state thermistors type units. They are extremely reliable.

Can you advise me on which immersion heater to buy?

We cannot advise on sizing or designing of cylinders as that is not our area of expertise. However, EMMA will work with any standard electric immersion element, but each load should be a max 3kW. For instance, if you want a 9kW immersion in total, then use three 3kW immersion elements rather than a single 9kW element.

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EMMA and your Aga, heat-pump, gas- or oil-fired heating

My hot water is provide by gas. I use the electric immersion only as a back-up (e.g. when gas supply fails). The gas hot water circuit and electric immersion element both serve the same hot water cylinder. I want to use excess solar power for immersion heating while continuing to top up with gas supplied hotwater heating. I only want to use grid electricity for water heating if the gas supply should fail. Can I do this?

Yes. This is a typical install.

How does EMMA operate alongside my gas- or oil-fired heating?

EMMA is supplied with its own temperature sensor. EMMA’s sensor is normally inserted near the top of the tank into the insulation to make contact with the cylinder. If an oil- or gas-fired boiler is also in use, it will have its own separate temperature sensor in the hot water cylinder. This governs when the boiler turns on and off based on the boiler’s timer settings and the water temperature. EMMA’s temperature sensor works independently of the oil/gas-fired boiler’s temperature sensor. This configuration allows you to:

– Use EMMA to heat the water whenever possible using electricity from your renewable generator
– Supplement this heating, when necessary, using the oil/gas-fired boiler. For instance, if there is not enough sun or wind to enable your generator to heat your water to the desired temperature on a particular day, your oil/gas-fired boiler will kick in at its set times to bring water up to the desired temperature. This means that, using your renewable electricity and oil/gas-fired boiler in tandem, you will always have enough hot water whatever the weather.

In the absence of an oil/gas-fired boiler, EMMA simply draws additional electricity from the grid to bring the water to the desired temperature for the time periods you choose if there isn’t enough electricity from the renewable generator. The advantage of an oil/gas-fired boiler is that is often more cost effective than using electricity from the grid.

Can EMMA be used to feed a log boiler accumulator?

Yes EMMA can be installed with log boiler accumulator tanks and works perfectly, all you need are one or more 3kW immersions in the tank and a probe pocket for the temperature sensor.

Can I use EMMA to heat the water to a higher temperature (thermostatically controlled) than the thermostat setting for gas, so the gas heating only ever kicks in if solar hasn’t taken the water up to the gas hotwater thermostat setting?

This should work. The stat for the gas should be seperate to the stat on the immersion (normally built into the immersion and is adjustable). Alternatively you can allow EMMA to control the temperature rather than the immersion stat by fixing the supplied temperature probe to the cylinder as per the installation manual. Lots of installs work like this.

I would like to get an EMMA for my PV system. However, I already get my hot water from my Aga. Is there anything else I could send the surplus electricity to?

You could send it to hot water in summer when you are not running your Aga, and to storage heaters in winter. This can be done with a simple ‘switch over’ switch once the season has ended.

I want to use the surplus electricity from my solar PV system to heat a swimming pool. The pool is currently heated via two air source heat pumps. Can we use you EMMA units to achieve this?

The EMMA will heat normal 3kW immersion elements which are separate to the heat pump. These immersions can contribute to the pool’s heating. The installation should be treated as if the heat pump isn’t there as far as electrical installation is concerned.

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EMMA and multiple loads / Minimising electricity exports

Can EMMA switch between multiple loads? Could I use an EMMA to power my Aga whenever I have a surplus, and then my immersion when the Aga is satisfied? And when the surplus is not enough to run the Aga can I easily override it and draw from the grid?

It is possible to have multiple loads for EMMA, such as your AGA and immersion, although we do not provide the mechanism to switch between them. Your installer will be able to organize this for you. EMMA always allows electricity to be drawn from the grid if you need it.

I have several electric based heating devices – like electric underfloor heating, hot water tanks, hot tubs, electic heaters etc. Can EMMA provide power for several heating/hot tub/hot water tanks etc simultaneously? Is there a limit to the number of hot water tanks etc that it can send power to? Can the power direction be chosen to where needed by the EMMA.

All the above is possible but is bespoke and will cost extra. Exact details need to be provided by the customer detailing the type and size of each load, whether there are any electronic controls and if they are individually wired from the fuse board. Then we / the Reseller will take a look at it and propose a system design.

Can I program EMMA so that NO energy is being exported – all is being sent to hot water? What happens if the hot water reaches the target temperature? Can I then program it to send electricity somewhere else?

You do not program a % of energy to be used onsite / exported, but, rather, a desired hot water temperature. If the tank reaches the desired temperature EMMA stops sending power to the immersion until the temperature drops. Any further electricity is exported. For instance, if 75% of the total energy produced by your generator is sufficient to heat the water to the desired temperature for the whole year, then by default the remaining 25% will have been exported because it has nowhere else to go.

However, you can connect additional resistive heaters to the EMMA unit providing that the total load doesn’t exceed the number of kW indicated as the Immersion/storage capacity for the particular model of EMMA, and none of the heaters contain electronic or electro-magnetic devices or motors (note that most underfloor heating systems and some electric Agas have electronic controls). These devices could then mop up that remaining 25% should you wish. We don’t provide the switch over facility to the other load but your local reseller/electrician should be able to organise this for you.

Note that EMMA will allow a small amount of power to be exported from time to time as we configure it to slightly lag household demand below the power being produced to avoid imports. We can allow more to be exported if you require it.

See How EMMA Works for a visual explanation of how EMMA works.

I really want to minimise grid exports from my renewable generator. Assuming my PV system’s output is sufficient, could I extend the wiring from EMMA so that it sends excess PV production to a heirarchy of loads – say initially a n immersion, then a storage heater, then batteries (e.g. for an electric car) and lastly an electric lawnmower or underfloor heating ?

A number of EMMA units have been installed in such a configuration. Some are being used to heat multiple hot water cylinders – switching from the first to the second when the first has reached the desired temperature , and the second to the third likewise. Some EMMA units are being used to send power to hot water cylinders, storage heaters and underfloor heating. Sending power to batteries is slightly more complex but can be done.

Can I use EMMA to power a socket that I can plug appliances into?

No. The output from EMMA can only be used for resistive heating/cooling loads that are directly connected to the EMMA. You can have a fixed switch between multiple loads though.

What sort of electric storage heaters does EMMA work with?

The storage radiators should not have electronic controls. Storage radiators with a bimetal strip contactor work perfectly. The storage radiators should not use anymore that 3kW of power. The following link contains details of the type of heater that EMMA works with:

This storage radiator requires one power supply from EMMA and one from the mains. The Control and filiment heater section is supplied from the mains. EMMA can charge the storage radiator section while you have complete control to turn on the filiment section if you require instant heat from the mains. EMMA also works with the older ‘boxier looking’ storage radiators with the bimetal strip stat.

Does EMMA work with IR Heating panels?

EMMA will drive IR Heating panels without difficulty providing that they don’t have electronic controls. If they have electronic controls you will need to check to see if you can power the IR Heating elements from EMMA and the electronic controls from the household mains. This may be possible. On certain sites we have used EMMA units to control power being supplied to IR Convector heaters in without any difficulty.

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EMMA’s Screens and Data Logging

What is the percentage figure on EMMA’s screen? According to the manual it is the percentage output from heating element – but what is this?

It means if the element is a 3kW element and the percentage says 50% then 1.5kW of power is being output by the heating element. If its 100% then 3kW are being output from the element. As the size of the element can vary EMMA displays a percentage rather than an exact power output on the screen.

What Data does EMMA log?

See p12 of the Operating Instructions. The “Meters” display on EMMA shows cumulative output, demand, import and export of electricity. If you read this regularly and enter the figures into a spreadsheet you can build up a picture of how EMMA is managing your generator’s output and household load.

Does EMMA measure how much power is sent to the immersion load?

Not specifically, EMMA only measures how much power is sent to the household demand of which the immersion is part.

Will it be possible to access more data from EMMA in future?

Possibly. EMMA already has comprehensive data loggers in it, but this is only accessible on EMMA GVS models for DNO purposes. The data is not available to standard users. In future we may produce a data access system that will plug into existing models of EMMA to allow you to record and access data remotely via a GPRS link.

Larger projects with EMMA GVS – limiting exports

I plan to use EMMA GVS to limit exports according to my DNO’s requirements. How do I get permission to grid connect my system?

You will need to submit a standard application to your DNO for connection of your generator along with a statement that you will be limiting power exports using an EMMA controller. Most DNOs are already familiar with EMMA, but if they request further detail please contact your reseller who will have the necessary information or be able to source it from us. For more, see EMMA GVS and Network Operators.

What does EMMA GVS do with the electricity when the generator is exporting too much? I read in the manual that ‘If the generator is exporting more than the permitted amount, then the EMMA will disconnect the generator from the grid automatically and reconnect when appropriate’. Where does the electricity go if the cylinder / secondary loads are maxed out and the EMMA is disconnected?

The EMMA does not get disconnected itself, it disconnects the generator from the mains so there is not electricity being generated.

What are the likely hot water requirements for my farm / dairy?

To get an idea of the hot water requirements for your farm/dairy, please see the attached calculation: Dairy hot water wash down requirements (Excel spreadsheet). EMMA GVS (Grid Voltage Stabilization) allows the export current of 16amps under G83 while the rest is sent to heating hot water on your site. Because EMMA GVS limits electricity exports it allows you to overcome any generator-size limitations imposed by your DNO. This makes it possible for you to install large PV arrays and Wind Turbines – and use them to meet your hot water requirements – in areas where it would not normally be possible.

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EMMA and Network Operators (DNOs)

How can EMMA reduced network disruption?

The distribution system operator (DNO) will also have reduced possibility of disruption to the network, especially if there are larger numbers of generators installed in the future. EMMA reduces network distruption and overvoltage events, leading to reduced network maintenance costs,increased output and reduced noise.

Which DNOs have approved EMMA for use on their networks?

EMMA GVS is approved by the following DNOs (Electricity Distribution Network Operators).

(updated 26 Feb 2012)

EMMA GVS is approved for use by Western Power Distribution (WPD, UK), Electricity North West (ENW, UK), Scottish Power Energy Networks (SPEN), Scottish & Southern Energy (SSE), Northern Power Grid (formerly CE-Electric) and ESB Ireland (Electric Ireland).

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EMMA says the hot water is at minus 1,000 degrees – why is this?

The HW temperature reading of -1000 indicates that either;
a) The lead to the temperature sensor is not connected to the correct pins on the controller. It should be connected across pin 5 and 6 (on the top counting from the left); or
b) The lead is not connected properly to the temperature sensor; or
c) There is a break in the lead between the controller and the temperature sensor.
It is unlike to be a problem with the temperature sensor itself as these are extremely robust. We haven’t had any failures yet.

EMMA stopped working at some stage during Christmas Eve night, but it started again a day later. What happened?

This was almost certainly the result of the holiday schedule being left at the default setting which was 00:01, 25/12 to 00:01, 26/12. During scheduled holiday periods the EMMA unit doesn’t send any power to the thermal store. You can change this setting using the holiday schedule option on the hot water settings screen – for instance, change it to 00:01, 01/01 to 00:02, 01/01…. which is effectively no holiday schedule.

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I have further questions, who should I contact?

Us! – Give us a call on 01386 871490 or fill in the form here:

Can I talk to one of your existing customers about EMMA?

No Problem, just give us a call on 01386 871490. You might also

You might also like this: How EMMA Works