Description: Daily granularity data from EMMA units. The EMMA unit is a device which is fitted in conjunction with Solar Photovoltaic (PV) installs in properties that have an immersion heater. The device diverts any excess PV generation energy, into the immersion heater to heat water, rather than send the excess electricity back onto the grid. This data set has 73 csv files, each with one participant's data held within it. Column A : date (dd/mm/yyyy) Column B : Output(kWh) is cumulative energy generated from PV Column C : Demand(kwh) is cumulative demand from the household COlumn D : Import(kWh) is cumulative energy imported from the grid COlumn E : Export(kWh) is cumulative energy exported to the grid COlumn F : HW(kWh) is cumulative energy sent to the electric immersion heater. This includes HWPV(kWh) COlumn G : HWPV(kWh) is cumulative surplus energy from the PV array sent to the electric immersion heater COlumn H : Output(kwh/d) is energy generated from PV for the 24 hour period. COlumn I : Demand(kwh/d) is demand from the household for the 24 hour period. COlumn J : Import(kWh/d) is energy imported from the grid for the 24 hour period. COlumn K : Export(kWh/d) is energy exported to the grid for the 24 hour period. COlumn L : HW(kWh/d) is energy sent to the electric immersion heater. This includes HWPV(kWh) for the 24 hour period. COlumn M : HWPV(kWh/d) is surplus energy from the PV array sent to the electric immersion heater for the 24 hour period. Notes : 1. The project participants all had electric immersion heaters, however there was gas central heating in a number of properties as well. 2. In June/July of 2015, EMMA units were upgraded from the 3G model, to the 4G model, so figures within the data will appear to reset. 3. Units record to 1 decimal place up to the value of 1000, where it records at 0 decimal places. As the columns reach the 1000 mark at different times, this can provide some precision issues on a small amount of the data. Background information on the NTVV project and the EMMA trial can be found in report http://data.ukedc.rl.ac.uk/simplebrowse/edc/Electricity/NTVV/Reports/SDRC_9.4b_Evidence_Report_1.0.pdf and at www.thamesvalleyvision.co.uk