andrew.bissell@sunamp.com @sunampltd 01875 610001 Optimising Electrical Systems via Smart Heat Batteries Presented at Energy Storage and Connected Systems 7 th February 2018
Takeaways and Problem Statement Top 3 key learnings or takeaways 1. What is a Heat Battery? 2. What is the benefit of making Heat Batteries smart? 3. Cost benefit analysis of Heat Batteries compared with other energy storage for balancing electric grids Problem Statement Electricity grids with renewables are intermittent at scales from weeks (high pressure system, no wind) to sub-second (frequency regulation) Heat demand is intermittent (scale of hours to seasons) and the amplitude is much greater than electricity demand Can we be smart and harness these two intermittences via something (say a smart heat battery) to solve both together?
Electricity intermittency Courtesy of Gridwatch
1 13 25 37 49 61 73 85 97 109 121 133 145 157 169 181 193 205 217 229 241 253 265 277 289 301 313 325 Heat demand intermittency versus electric demand Courtesy of Dr Robert Sansom (personal communication & thesis) and Richard Lowes (twitter: @heatpolicyrich & blog) It looks impossible for electricity to meet the Heat demand. But a more granular view shows this is a couple of peaks of demand per day when heating is on and people are showering. This does not have to be met from instantaneous gas heating. Stored heat smooths it to average. 300 250 200 150 100 50 0 Week of 1-7 Feb 2010 Sansom, R. (2014), Decarbonising low grade Series1 heat for a low carbon future: A thesis subm to Imperial College London for the degree of Doctor of Philosophy. London: Imperial Co http://blogs.exeter.ac.uk/energy/2017/07/10/is-the-peak-heat-issue-all-its-made-out-to
Heat demand intermittency versus electric demand Courtesy of Dr Robert Samson (personal communication & thesis) and Richard Lowes (twitter: @heatpolicyrich & blog) Sunamp own re-interpretation of Dr Samson s 2010 heat demand data is based on averaging to distributed thermal storage (green curve). Assuming COP 2.75 heat pump is used to charge thermal storage, the extra electricity demand is the blue curve. The problem looks manageable. i.e. << less than doubling electricity demand, if every building has a heat pump with storage. More storage should enable the increase to come from moments where the grid has excess renewable electricity to offer. Sansom, R. (2014), Decarbonising low grade heat for a low carbon future: A thesis subm to Imperial College London for the degree of Doctor of Philosophy. London: Imperial Co http://blogs.exeter.ac.uk/energy/2017/07/10/is-the-peak-heat-issue-all-its-made-out-to
Sunamp Heat Battery Vision Disrupt the hot water cylinder market with a better, smaller, more efficient heat store that fits beautifully into small, modern living and working places. Return storage to homes that, because of the trend to combi boilers, are becoming storage poor. Support the transition to intermittent renewable energy especially PV on buildings, wind in the Grid and heat pumps.
How do they store heat? High Energy Density Melting and freezing a PCM (Phase Change Material) stores 3-4 times as much energy as heating water Hand warmer (melts at 58 C) Sunamp & University of Edinburgh Collaboration: Technical Innovations Overcame instability of original material <100 cycles before failure Patented SU58 >35,000 cycles (so far) Wouldn t always solidify (no heat) SU58 always solidifies and releases heat Slow heat transfer (no showers!) Heat exchanger inside = high flow rate hot water High Energy Density Retains PCM compactness when scaling to heat battery size (non-trivial). High Power High power heat exchanger inside, so heat can be rapidly charged into the heat battery and equally quickly extracted high rate discharge. This means can deliver 20+ litres per minute hot water for showers This means can rapidly warm a heating system (comfort & SAP points) Modular Cuboid and able to stack like Lego Cost-Effective Comparable price to Hot Water Tanks Lower Total Cost of Ownership Much lower cost than electric batteries Gen 2 Heat Battery
Wide range of Storage Temperatures Sunamp Heat and Cool Batteries can be filled with different PCMs to optimise each application Freezing Cold storage Air conditioning Waste heat recovery & pre-heat Hot water Space heating Industrial process heat Steam generation -26 (-15) -18 (0) -14 (7) -5 (23) 4 (39) 14 (57) 34 (93) 58 (136) 83 (181) 88 (190) 117 (243) 188 (370) 253 (487) -25 (-13) -21 (-6) -15 (5) -10 (14) 0 (32) 8 (46) 28 (82) 43 (109) 114 (237) 167 (333) T, C ( F) Chiller Low temp heat pump Solar thermal High temp heat pump Biomass, gas, propane, oil CHP/Co-Gen Organic Rankine Cycles Waste Heat Thermal Buffering Sunamp PCMs are internally developed, inorganic, non-flammable materials. Values indicate phase change temperature. They are at different level of development and not all commercially available today.
Proven via cycle testing latest results July 2015 January 2018 Previously undetectable degradation rate just becoming apparent after ~2.5 years and ~35,000 cycles. Peak rate 120 cycles/day (5 minute charge, 7 minute discharge & repeat) Average lowered to ~35 cycles/day due to periods when cycle rig was inactive (e.g. Moving premises). Further testing expected to confirm trendline. Courtesy of Dr David Oliver (Edinburgh), Materials Scientist & Dr Kate Fisher (Edinburgh), Composite Materials Scientist at Sunamp
Electric batteries compared with Heat Batteries cycle life 100% DOD Sunamp Charged/discharged at ~6C (10x higher power) Typical Lithium Ion Battery
Electric compared with Heat Batteries on cycle life 4000 8000 12000 16000 20000 24000. 28000 32000 36000 What do we need to do with each technology to get 36,000 cycles? ~10 cycles per day for 10 years (high utilisation balancing) or 3 cycles per day for 30 years (e.g. Economy 10 off-peak) Lithium Ion, cycled to 80% DOD, needs to be replaced 8 times average capacity 90%; terminal capacity 80% Sunamp heat battery, cycled to 100% DOD, not replaced average capacity 97.5%; terminal capacity 95% (tested to date) CAPEX implication LCOS implication Lithium Ion list price (best) ~ 350/kWh / 80% DOD => 437.50/kWh useable over total 9 units to get 36,000 cycles => 3,150/kWh => 8.75p/kWh_cycle Sunamp heat battery list ~ 200/kWh / 100% DOD 16x 16x => 200/kWh useable over 1 unit to get 36,000 cycles => 200/kWh => 0.5p/kWh_cycle
Other Key Parameters Cost of CAPEX per capacity and LCOS are good measures of how much energy can be transacted for how much money. But to stabilise intermittent grids as they fill up with wind energy, PV solar, etc; to provide ancillary services to TSO or DSO; to rapidly respond to rising & falling output of a large PV array behind-the-meter to avoid export we also need low CAPEX for the charging power that can be dispatched. Electrically charged Gen 3 heat batteries do well.
Proven by long duration trial (2013 to date) Trial in seven homes funded by DECC Off-peak Economy 10 electricity Air source heat pump (2.5-3x COP efficiency) Heat Battery compact storage provides time-shift: run heat pump when its cheap, use heat/hw at any time Easy retrofit installation In service for 5 winters (some still with Gen 1 heat batteries, some upgraded to Gem 2) Heat Pump Central Heating SunampStack Hot Water
Trial Results Results and Benefits: typical running costs savings range from 45% to 57% carbon emission reductions range from 17% to 36% Spec 40 kwh Sunamp heat store Air Source Heat Pump (Daikin) Works to -25C CASE A From Electric Heat and Water CASE B From ETS and Electric Hot Water CASE C From Electric Heat and Water CASE D From Gas Heating & Hot Water This is a 2-bedroomed house with 2 working occupants. They are heavy hot water users having 2 deep baths in the morning and 2 deep baths in the evenings This is a 3 bedroomed house lived in by a young working couple, their heat and hot water usage is normal. This household had night storage heater. Comfort has improved. This is a one-bedroom house, semi detached bungalow. The occupier is an retired man who looks after his grandchildren in the early evening so the house must be warm - Achieved This is a 5-bedroomed house with 2 working occupants, 1 teenager and 1 visiting young adult. Previously mains gas heated Annual Savings on Heat and Hot Water kwh saving Bill saving CO 2 Saving 59% 56% 29.1% 8,404 KWh 602.17 1259 KgCO 2 Annual Savings on Heat and Hot Water kwh saving Bill saving CO 2 Saving 40% 45% 36% 4,921KWh 414.78 1596 KgCO 2 Annual Savings on Heat and Hot Water kwh saving Bill saving CO 2 Saving 49% 57% Not 3,291 KWh 325.91 Available Not Available Annual Savings on Heat and Hot Water kwh CO Bill saving 2 saving Saving 77% 50% 46% 28,476 3645 926.77 KWh KgCO 2
Proven via large scale trial Products developed and manufactured by Sunamp near Edinburgh Over 1000 tenants positively impacted with 20%+ bill and energy savings 766 Gen 2 Heat Battery Products installed in over 600 homes by Q1 2016 In daily service for two years with high reliability providing heat and/or hot water to circa 2000 people 4.4 MWh total storage in 2028 Heat Battery 'Red Cells'
Electric battery compared with heat battery BYD Lithium-ion battery 30.7dm 3 26.5dm 3 Sunamp Heat Battery 38kg 130mm 2.5kWh 2.5kW 2.5kWh 35kW 6,000 cycle life (to 70% capacity) >35,000 cycle life (to >95% capacity) 16% final household energy consumption is electricity Appliances 12% Lights 4% Cooking 3% 81% final household energy consumption is heat Space heating 62% Hot water 19% % household final energy consumption in UK United Kingdom housing energy fact file, 2012 maurizio.zaglio@sunamp.co.uk
Smart heat batteries Hot water Space heating Space cooling Shrunk 4 times smaller Hot water tank Gen 3 heat battery Thesis: Aggregates of heat batteries in just hundreds of buildings can deliver meaningful capacity (MWh) and power (MW) to balance the electric grid while supplying all needed heat and hot water. Smart interaction with grid & behind-the-meter renewables Customer engagement
Preview of Gen 3: Widest range of Applications Grid Electricity Natural Heat Fossil Fuel or Biomass Solar Energy Third Party HVAC Compatibility Boiler (Gas, Combi, Oil, Biomass, ) Heat Pump (Air, Ground, Water, ) Controllers (Nest, Honeywell, ) Solar Panels (PV or Solar Thermal) PV AC Controller (Power Diverter, Solic 200, ) Heat Pump Boiler PV or ST Sunamp Controllers UniQ System Controller UniQ PV DC Controller UniQ PV AC Controller SunampOS (DSM) Launching Q1 2018 Mains AC Electricity PV AC Electricity Thermal PV DC Electricity Heat Battery Options Capacity (3, 6, 9, 12, 60 kwh) AC or DC elements (various kw) PV AC Controller Inverter Heat and/or Hot Water
Supporting the electricity Grid Reducing Demand PV self-consumption absolute reduction Grid Electricity Natural Heat Solar Energy Use of Heat Pumps relative reduction typically COP 3 (1 unit of electricity gives 3 units Heat) (Sunamp / DECC / BHA trial results: 45 60% energy and bill reduction) Heat Pump PV or ST Flexing Timing Drawing electricity only at low-carbon times (National Grid API predictive) Even simple off-peak like Economy 10, with only resistance electric heating and low Sunamp heat loss, gives benefits of enabling more intermittent Renewable electricity into the Grid (and reducing demand for dispatchable coal and gas) Mains AC Electricity PV AC Electricity PV AC Controller Thermal PV DC Electricity Inverter Heat and/or Hot Water
small loads (< 100kW) Aggregators (100kW+) Electricity Grid Is there a missing piece? The GAP large loads Transmission System Operators (TSO) Distribution System Operators (DSO) Aggregator (e.g. Aggregator (e.g. Aggregator (e.g. Aggregator 1 Aggregator 2 Aggregator 3 Open Energi) Open Utility) Vcharge/OVO)) Micro Aggregator SunampOS Runs in its own processor with memory, security and communications Links via API to the Heat Battery controller for state of charge, state of health and to issue commands (e.g. Charge now at 7kW ) Aggregators can plug in their own Apps via an API to offer their services (the world doesn t need another aggregator) and aggregate up hundreds of small units securely to their larger aggregation scale Delivers user functionality like statistics, metering, control Sunamp are inviting partnerships around this needed piece with other vendors including aggregators and energy storage companies e.g. Electric batteries
Sunamp Highlights Sunamp Heat Batteries are probably the world's most energy efficient Thermal Stores disruptive to hot water tanks, complementary to HVAC equipment, electric batteries, renewable energy & intermittent grids Cost parity with water tanks today with performance superiority. Much lower cost per MWh and cost per MW than lithium-ion batteries (for Heating and Hot Water applications) 17 patents granted, 74 in pipeline across all key countries materials, heat battery, system, applications DECC funded trial of Gen 1 Heat Battery systems in 2013 (still in use today) Over 900 systems installed using Gen 2 Heat Batteries (trial and private sale) Gigafactory manufacturing capacity coming online for Gen 3 (1 GWh per year)
Conclusion Top 3 key learnings or takeaways 1. What is a Heat Battery? A highly competitive energy storage that addresses the largest demand (heat) and provides flexibility of charging (electric) 2. What is the benefit of making Heat Batteries smart? Aggregate flexible electric demand to solve the heat and electricity conundrums 3. Cost benefit analysis of Heat Batteries compared with other energy storage for balancing electric grids CapEx and LCOS benefits against market leaders in range 2x 32x depending on your criteria (MW, MWh) Many heat batteries will be installed for normal HVAC reasons, e.g. Provision of hot water, so over-sizing slightly to provide flexibility is even less expensive Solution Statement Can we be smart and harness electricity and heat intermittences via something (say a smart heat battery) to solve both together? Sunamp believes an emphatic Yes We are prepared to work with partners (several in play already) SunampOS will deliver a flexible, no lock in solution that is aggregator friendly
andrew.bissell@sunamp.com @sunampltd 01875 610001 Optimising Electrical Systems via Smart Heat Batteries Presented at Energy Storage and Connected Systems 7 th February 2018