26 th April 2007 Integrating Composting Toilets within the Concept of an Eco-Beach Richard Forbes - Physics Gemma Gotch - Chemistry Panagiotis Grigorakis – Electrical Engineering Judith Martyns-Yellowe – Environmental Engineering

26 th April 2007 Overview Background Eco-Beach Concept Project Objectives Beach Classification Feasibility of Wind & Solar Composting Theory ESP-r Model & Results Composting Toilet Design Environmental & Economic Impact Conclusion

26 th April 2007 Waste on Beach - Mainly landfilled by local authorities - Estimated £585,000 spent on beach cleaning in 2006 Facilities - Few toilets and kiosks (centralized) - Restricted locations Background

26 th April 2007 Eco-Beach Concept A framework that delivers a comprehensive approach to sustainable beach management Key: = Education = Kiosk = Composting Toilet = Recycling Point = Transport = Access Route

26 th April 2007 Project Objectives Define Eco-Beach Concept Develop a beach classification guide Feasibility Study of Wind & Solar Energy Design a composting toilet

26 th April 2007 Beach Classification Guideline for determining requirements of an Eco-Beach. Category 1 Category 2 Category 3

26 th April 2007 Beach Classification 2 Category 1: Remote Beach, South Harris Best Environmental option to leave beaches as they are. Category 2: Ayr Beach Composting Toilet, Recycling facilities, Access for disabled use, Educational notices. Category 3: St Andrew’s (West Sands) Composting Toilets, Recycling facilities, public transport service, Educational activities on the beach, sustainable kiosk possibility.

26 th April 2007 Wind and Solar Power Wind PV –Good match with demand –Low intensity (and structures are small) Solar Water Heating –Good match with demand

26 th April 2007 Wind and Solar Structures requiring power: Kiosk, Ice Cream Van, Toilet Application Electrical Appliance Rating Renewable Supply Option Area required (m 2 ) Cost (£’000s) Cooking3 kWBiofuelN/A Hot Water1 kW Solar Collector 0.5 Ice Cream Maker 800 WPV8.46 Cold Storage 100 WPV1.41

26 th April 2007 Supplying Cold Storage

26 th April 2007 Composting Toilet Composting Process: Heat produced can result in T ~ 70 o C Composting toilets don’t achieve this Composting Pile Micro Organisms Finished Product O2O2 Heat CO 2 H2OH2O Human Waste

26 th April 2007 Composting Toilets Can high temperatures be achieved? –Insulation –Optimal conditions (moisture, C:N ratio, air flow) Insulation requirements determined by dynamic modelling and experiments Conditions controlled by features of overall design Calorific Value ~ 25 MJ / kg

26 th April 2007 Composting Peak heating power ~ 84 W / kg

26 th April 2007 ESP-r Model Objective Construction 250W Gain – 3kg of faeces Airflow – 36 m 3 /hr Control – °C Insulation

26 th April 2007 ESP-r Results Mean temperature is 62 °C Insulation → 10cm polystyrene Compost temperature Mean temperature Ambient Temperature

26 th April 2007 Composting Toilet Design Key considerations in our design Maintaining optimum conditions for a thermophillic process Low energy toilet Ease of maintenance Multifunctional A finished product that is safe to handle Achieving optimum conditions Moisture control – Diverting and composting urine Aeration – Ventilation and Exhaust powered by 10W PV panel C:N ratio – Saw dust provides the carbon required to maintain a C:N ratio of 30:1 Temperature – Insulating chamber with 10cm polystyrene boards Design of a saw dust dispenser

26 th April Sawdust flusher All dimensions in meters Dry urinals Urine composter

26 th April 2007 Benefits of the Eco-beach Concept Environment Reduced energy consumption Pollution and nutrification reduction Re-use of waste, less use of landfills Improved environmental & sustainability awareness

26 th April 2007 Benefits (II) Socio-Economic Enhanced tourism More revenue for councils Improved accessibility Alternative uses for beach litter – waste becomes a resource Cost of land filling waste is reduced considerably

26 th April 2007 Limitations & Recommendations Lack of accurate data from local councils Experimental conditions Design of an Eco centre for educational activities, café, shops which would be powered entirely by renewable supply Comprehensive cost study of waste management on the beach Consider other applications for the toilet such as festivals, construction sites Sophisticated control system

26 th April 2007 Conclusions Defined the concept of the Eco beach Beach classification model Solar resource most suited for the beach - there are limitations High temperature composting is possible without heaters Toilet design

26 th April 2007 Thank you for listening………… Any Questions?

26 th April 2007 Food Human Waste Toilet Compost

26 th April 2007 Drinking Water Fresh Water Energy, Chemicals Foul Water Human Waste Food Energy Contaminated Water Water for discharge to sea Sludge Anaerobic Digestion Aerobic Digestion Compost

26 th April 2007