Oxford case study on storing and sharing solar-generated electricity: Insights from Project ERIC Energy Storage Summit, 28 April 2016 Twickenham
Drivers for the project from the local authority s perspectives and experience with the project Debbie Haynes Oxford City Council
Getting started (in Rose Hill) Fear of the new But Lots of inspiring and bright people Strong community input Area of high % of social housing Strong joint commitment and drive Previously had piloted 5 solar PV and 2 Maslow installs So OCC commitment of 30 solar PV installs and batteries
Oxford City Council: Aims project met Reduce energy bill of tenants Generate long term income Reduce carbon footprint of the city Increase sense of community and positive environmental interest Support innovative research project Promote community energy
What was/is it? 49 Solar PV installs into our social housing (Joju Solar) 49 battery installs (Maslows) Some LED lighting (DC powered) Data monitoring and interviews
What this actually involved Desktop PV analysis of 2kWp and SW to SE orientation/ no shading = PV shortlist Roof replacement/ tenant interest checks Property surveys - numerous Building surveyor managed project for OCC Tenant liaison officer (part time) supported Bioregional Regular project meetings coordinated Considerable input in terms of resources Sometimes varied from specification (1.25 to 3kWp)
Council resources Building Surveyor Project managed all work/surveys Technical/legislative liaison Electrical/structural issues and checks Tenant liaison officer Coordinated surveys Produced literature with visual aids. Promote benefits and understanding On hand to deal with problems/worries
What we learned (site) Site survey must quickly follow desktop survey Access to homes difficult Number of surveys high and intrusive Tenants may not want PV/batteries our housing project, their home Metering/ broadband problems Electrical checks vital Stick to specification Generally good feedback even PV envy
What we learned (broader) Additional requirements of Maslow battery Local area need to be fair (specification) Trial means teething problems Data protection agreements Call outs/maintenance issues Tenant liaison vital Can t predict everything
Also PV and Moixa batteries in Rose Hill Community Centre
project eric re-energising communities Moixa Technology Maslow energy storage system GridShare TM VPP cloud platform Chris Wright CTO Moixa Technology chris@moixaenergy.com www.moixatechnology.com www.meetmaslow.com
Moixa hardware and aggregation platform Proprietary Maslow hardware Software GridShare aggregation platform Analysis and control tools Trading to energy markets The Moixa Technology offering: The Maslow proprietary hardware, all-in-one energy-storage solution The GridShare SaaS platform that monitors and controls distributed energy resources in the field, and aggregates them into groups to trade on to the energy market.
GridShare VPP cloud platform National Grid dashboards Maslow systems TCPip 3rd party systems integration Bi-directional EV charge Chademo - Nissan HyperCat energy integration analytics
Project Eric dispatch: Substation monitoring Testing local grid effects: 28th April test dispatch of a small subset of 20 houses, 1hr dispatch event. This is visible on the sub-station monitoring installed by SSE PD for the project.
Revenue & payback model The revenue model below illustrates a financed system over 10 years @ 6% for a household with an existing solar PV system.
Example revenue steam: trading 24 Oct 15 Average October day 120/MWh trading range 16 May 15 High wind day, market is long 70/MWh available Payment to take energy
Project evaluation to date Prof Rajat Gupta & Dr Adorkor Bruce Oxford Brookes University
Evaluation methodology Monitoring: Household electricity consumption Solar PV electricity generation Contribution of smart electricity storage Conducting dwelling and household surveys Undertaking energy audits of electrical appliances Data for evaluation obtained from multiple sources
Project evaluation and findings to date Evaluation elements: Dwelling and household characteristics Feedback from household interviews Household baseline electricity consumption PV generated electricity Contribution of smart electricity storage household and community level
ERIC dwellings in Rose Hill 82 households in Rose Hill 74 social rented 8 owner-occupied All households have solar PV systems (1.5 4kWp) 2kWh Maslow battery installed in all households 60 out of 82 households interviewed (73% response rate)
Dwelling and household characteristics Bungalows Older dwellings Flats New dwellings Gas central heating in all dwellings Energy efficiency rating B to D Variety of household sizes - 1 to 8 householders Variety of household types e.g. families with dependent children, single person over 65 Variety of occupancy patterns e.g. always occupied, evenings and weekends only 55% of the households are always occupied
Householders energy attitudes and feedback Energy attitudes 75% of ERIC householders are concerned about rising energy prices 80% frequently think about their household energy use 72% are concerned about climate change 60% are concerned about energy supplies Feedback Different stakeholders have different reasons for participation in Project ERIC owner-occupied householders are interested in promoting new technology Generally good experience with the installation of the Maslow unit
Household baseline electricity use Average daily household electricity use (kwh) Average daily household electricity use range from 2.9kWh to 21.7kWh Median = 6.9kWh, Mean = 7.3kWh 24 22 20 18 16 14 12 10 8 6 4 2 0 H64 H75 H17 H34 H74 H63 H07 H67 H12 H68 H65 H73 H35 H70 H59 H44 H20 H84 H62 H83 H71 H11 H23 H05 H79 H55 H21 H30 H81 H36 H37 H14 H18 H16 H49 H15 H60 H39 H33 H10 H38 H40 H31 H46 H42 H25 H53 H24 H57 H09 H19 H85 H80 H08 ERIC Households
Characteristics of electricity use Weak correlation between household size and average daily electricity use (r 2 = 0.33) Weak correlation between number of appliances owned and average daily electricity use (r 2 = 0.27) 25 Ave daily household electricity use Number of householders 10 25 Ave daily electricity use Number of appliances owned 50 Average daily household electricity use (kwh) 20 15 10 5 9 8 7 6 5 4 3 2 Number of householders Average daily household electricity use (kwh) 20 15 10 5 45 40 35 30 25 20 15 10 Number of appliances owned 1 5 0 H64 H75 H17 H34 H74 H63 H07 H67 H12 H68 H65 H73 H35 H70 H59 H44 H20 H84 H62 H83 H71 H11 H23 H05 H79 H55 H21 H81 H30 H36 H37 H14 H18 H16 H49 H15 H60 H39 H32 H10 H38 H40 H31 H46 H42 H25 H53 H24 H57 H09 H19 H85 H80 H08 0 0 H64 H75 H17 H34 H74 H63 H07 H67 H12 H68 H65 H73 H35 H70 H59 H44 H20 H84 H62 H83 H71 H11 H23 H05 H79 H55 H21 H81 H30 H36 H37 H14 H18 H16 H49 H15 H60 H39 H32 H10 H38 H40 H31 H46 H42 H25 H53 H24 H57 H09 H19 H85 H80 H08 0 ERIC Households ERIC Households
PV generated electricity 4000 Approximately 91MWh of electricity has been generated since April 2015 PV generated electricity (kwh) 3500 3000 2500 2000 1500 1000 500 0 H85 H01 H02 H04 H06 H07 H09 H10 H11 H12 H13 H14 H15 H16 H17 H18 H19 H20 H21 H22 H25 H26 H27 H28 H29 H30 H08 H24 H23 H80 H81 H66 H67 H70 H71 H72 H73 H74 H75 H76 H77 H65 H68 H59 H60 H61 H62 H63 H64 2 kwp Generation in 1 year Generation in 1 year: Apr-15 - Mar-16 2.5kWp 2.753.25 3.5 3.8 4 1.5kWp 2kWp 3 kwp 2.5kWp Generation in 7 months Generation in 7 months: Sep-15 - Mar-16
Contribution of smart electricity storage household level Electricity consumption and generation (kwh) 1.2 1 0.8 0.6 0.4 0.2 Household consumption (with Maslow) Household consumption (without Maslow) 0 00 02 04 06 08 10 12 14 16 18 20 22 Hour of day PV generation Charge in Maslow 1) Electric charge in the Maslow starts to increase when PV electricity generation is greater than household consumption 100 80 60 40 20 0 Electric charge in Maslow (Ah) 3) Saving from use of stored electricity (reduced grid electricity demand) 2) Power from the Maslow is discharged when PV electricity generation is less than household consumption
Contribution of smart electricity storage community level (n=40) Electricity consumption and generation (kwh) Total electricity consumption (with Maslow) Total PV electricity generation Total electricity consumption (without Maslow) Total charge in Maslow 40 35 30 25 20 15 10 5 0 00 02 04 06 08 10 12 14 16 18 20 22 Hour of day 4000 3500 3000 2500 2000 1500 1000 500 0 Electric charge in Maslow (Ah) Aggregated electricity consumption and generation (March 2016) Total consumption Total PV generation Total energy from Maslow Total PV electricity consumed (assuming 50% used + storage) % increase in PV electricity consumption % reduction in peak grid demand 9,831 kwh 5,219 kwh 656 kwh 3,266 kwh 12.6% 11.2%
Key findings There is a good range of households participating in Project ERIC e.g. tenure, household size and occupancy patterns. Multiple sources of data have been useful to ensure reliability and accuracy of monitored data. There is currently limited householder understanding of the installed systems, particularly of the battery units, in the social-rented households. Relevant feedback on the performance of the technologies will help householders in optimising their behaviours in order to maximise the energy savings.
Thank you! Oxford Brookes University Low Carbon Buildings Group Prof Rajat Gupta rgupta@brookes.ac.uk Oxford City Council Debbie Haynes (Energy Efficiency Projects Officer) dhaynes@oxford.gov.uk 01865 252566 Moixa Technology Ltd Chris Wright (CTO) chris@moixaenergy.com www.moixatechnology.com www.meetmaslow.com