Sustainable water solutions for urban homes Highgate Homes
Sustainable water solutions for urban homes Highgate Homes March 15 th 2017 Cath Hassell cath. hassell@ech 2 o. co. uk @Cath. Hassell an ech 2 o cpd 2017 www. ech 2 o. co. uk
Who are ech 2 o and what do we do? an ech 2 o cpd 2017 www. ech 2 o. co. uk
Sustainable water solutions for urban homes What we will cover What we won’t cover • Water efficient bits • Why engineers hate of kit plumbers • Renewable ways • Why Leicester City to supply hot water have decided to start • What to do with playing properly rainwater an ech 2 o cpd 2017 www. ech 2 o. co. uk
Understand the carbon load of water • CO 2 emissions from 1 m 3 of hot water heated by a gas condensing boiler are 7 kg. CO 2 an ech 2 o cpd 2017 • It takes 1. 2 k. Wh of (mostly) electrical energy to supply and treat 1 m 3 of mains water. • This results in 0. 7 kg of CO 2 emissions per m 3 of mains water used • Carbon emissions from the water supply industry are only 0. 6% of total UK emissions but when we add domestic hot water use this figure rises to 6%. www. ech 2 o. co. uk
Water efficiency solutions • Dual flush WCs. • Flow regulation at taps and shower heads. • Automatic taps. • Close grouping of appliances to boiler or hot water cylinder • Hot fill dishwasher if heating hot water by gas or solar an ech 2 o cpd 2017 • Result in large water and/or CO 2 savings. • Low cost. • Fast payback. • Simple to install. • Little required maintenance. www. ech 2 o. co. uk
Hot Water an ech 2 o cpd 2017 www. ech 2 o. co. uk
Solar Thermal an ech 2 o cpd 2017 www. ech 2 o. co. uk
Solar Thermal • Can supply between 50 -70% of a household's yearly hot water demand – 4 m 2 collector and 250 litres stored water • Require a south west to south east unshaded aspect and space for cylinder • Use a solar rated dual coil cylinder, vented or unvented • Use intelligent controls to optimise solar gain • Collectors can be flat plate or evacuated tubes • Panels can be roof integrated or above roof mounted an ech 2 o cpd 2017 www. ech 2 o. co. uk
Solar PV to heat water • • an ech 2 o cpd 2017 The Immersun switches PV generated electricity into the hot water cylinder instead of exporting it. £ 350 plus installation v £ 4, 000 (and rising) for solar thermal www. ech 2 o. co. uk
Heat recovery from wastewater • • • an ech 2 o cpd 2017 As hot water runs to drain it can be used to heat incoming cold water In domestic situations use for waste water from showers. Requires 2 -2. 5 m vertical space under the shower tray Tests in NL on the Recoh-vert RV-3 have shown 62% of waste heat recovered with a flow rate of 7. 5 l/min Can fit to two showers, one of which can be an electric shower Now costs less than £ 500 to buy www. ech 2 o. co. uk
Rainwater that falls on or near the building an ech 2 o cpd 2017 www. ech 2 o. co. uk
We must decouple rainwater from combined sewers an ech 2 o cpd 2017 www. ech 2 o. co. uk
Solutions End of pipe solutions • Build a ‘super sewer’. Expensive (£ 4. 2 bn at 2012 prices) Front of pipe solutions • Collect and use rainwater outside • Depave front gardens - alternatives are gravel, permeable paving, reinforced grass areas or return to a garden an ech 2 o cpd 2017 www. ech 2 o. co. uk
Decouple rainwater from the sewers rainwater harvesting • In the UK rainwater is classified as fit for purpose for WC flushing, washing machines, grounds watering. • Generally, rainwater harvesting is better suited to larger buildings • Difficult to retrofit for internal use, so collect and use outside an ech 2 o cpd 2017 www. ech 2 o. co. uk
Wide variety of storage solutions an ech 2 o cpd 2017 www. ech 2 o. co. uk
Decouple rainwater from the sewers - rain gardens and rain garden planters • Yellow flag, purple loosestrife, bistort, yellow cone flowers and speedwell are colourful plants that survive well in a range of moisture conditions. • www. raingardens. info for a UK rain gardens guide an ech 2 o cpd 2017 www. ech 2 o. co. uk
an ech 2 o cpd 2017 www. ech 2 o. co. uk
What happens when it rains an ech 2 o cpd 2017 www. ech 2 o. co. uk
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