Wednesday, June 21, 2006

Waste Vegetable Oil for Dummies - Part 3

Well they said it was "Just Three Steps to Heaven", and here is the third installment in my own personal journey into using waste vegetable oil for powering my home in Suburban Surrey.

Regular readers will remember how I spent the tail end of last year minimising my fuel bills. It must be the Scottish blood in me that I inherited from my mum. My electricity savings are about 20% and my gas consumption is down by 50% since 2000, when I moved to this house.

To be successful with renewable fuels you have to work at your religion, be it, either sawing or chopping firewood, or collecting and filtering waste vegetable oil, these ideas only work out if we work at them.

The engine installation is far from complete, and it lacks the final plumbing system that will effectively tie it into the hot water and heating systems of the house. Today I made a start on providing the engine with its own hot water storage cylinder see photo- which is also shared with my solar panel. When either the panel heats up, or the engine is started and is up to running temperature, the circulation pump switches on and starts to heat up my domestic hot water. It has the added bonus that the solar panel can be used to pre-heat the engine block, making it easier to start directly on waste vegetable oil.

Over the next few months I will complete the installation in readiness for the winter season. Anyone in the south east of England wanting to find out more about this system can contact me at

Waste Vegetable Oil for Dummies - Part 2

Here's the filter barrel that Tim and I made at the weekend. It took about an hour and within no time at all was filtering the oil to the standard required to run a diesel engine.

Today is Midsummer's Day - and there is no better time to start thinking about your renewable home heating project for the next heating season.

Within 90 days, it will be time to turn on the central heating system again, and now you have the option of continuing to pay the utilities for over priced, non-sustainable fossil fuels, OR break free from those shackles, and generate your own heat and power entirely from waste vegetable oil. A lot of UK householders are going to get a big shock when they see their utility bills next January!

My own renewable heat and power installation received a boost this week when Tim came over from Ireland and gave me a crash course in waste veg oil filtering.

Waste veg oil is rather unpleasant stuff, but a whole lot nicer than petrol or diesel. Once you get into a routine of collecting oil from pubs and restaraunts - religiously every week (so as not to piss off the owner or chef), and keeping your filter barrel topped up on a daily basis - just 5 minutes per day, then the rest is child's play.

Today was a rather dull day and the solar water heater doesn't perform too well when it's cloudy -so I rigged up a cable direct from the Lister alternator to my 3kW immersion heater in the hot water tank, and ran the Lister for a couple of hours on filtered waste vegetale oil - courtesy of my local pub.

It soon became apparent that the alternator had power to spare, so the dishwasher was plugged into a 30 foot extension cable and this was then plugged into the Lister alternator.

I am now in the process of installing a 20 gallon hot water / cooling tank, adjacent to the Lister, so that it has plenty of coolant capacity, and it can heat my domestic hot water from its coolant via a copper coil in the local coolant tank.

It should be remembered that a typical diesel engine converts on third of its fuel energy into mechanical power and the other two thirds appear as waste heat via the exhaust and coolant circuit. If it's heat that you are after - then there is no better way of converting waste vegetable oil into heat than using a slow speed diesel engine. No worries about Turk or Babington burners in this household!

If you want to follow this route, you need to pass a simple test: Just stick your forearm up to the shoulder into a barrel of rancid veg-oil gloop to tighten a leaking drain tap. If you can cope with that - then you are en route for sustainable free fuel forever!

We hope to have some of this technology on display later this summer at the Great Dorset Steam Fair.

Waste Vegetable Oil - For Dummies - Part 1

On Saturday evening, fellow renewable fuel enthusiast, Tim from Tang arrived for the weekend, and we set about getting me properly set up for filtering waste vegetable oil.

Tim had driven the 400 miles or so from Athlone in central southern Ireland, in his veg oil fuelled Mitsubishi jeep (left), and I had offered him all the veg oil he needed to get home - provided that we could filter it.

Using a plastic 208 litre drum with a 250mm hole cut in the top with a jig-saw, Tim made a filter bag support from an old plastic flower pot with it's base removed, and a plywood cover to hold the filter bag in place.

We then fitted a oil draining tap about 8" up from the bottom of the barrel, and a water draining tap at the very bottom.

Now for the fun bit! I already had 10 cans of waste veg oil that had been collected last year from a local pub, and had been settling for a year. Tim up-ended these into the filter barrel until the point where the whiteish looking animal fat just started to appear at the mouth of the can - you don't want that in the mix, so it was time to stop pouring.

We poured about 80 litres of WVO into the tank, and then emptied it via the drain tap into 3 empty cans. We then poured these back into the top of the filter for a second pass through the now wetted filter bag.

The following morning we extracted about 70 litres of perfectly filtered veg oil, 20 litres of which, Tim poured straight into the tank of his Mitsubishi jeep (photo above). The rest I kept in the filter tank for the Lister engine generator.

Thanks to Tim Dawson-Stanley for all his help and enthusiasm over the last few days. He specialises in the supply of vegetable oil fuelled combined heat and power systems and vegetable oil conversions for vehicles in southern Ireland. Tim can be contacted at

The Lister has been running for several hours for the last two days on the filtered waste vegetable oil - straight from the filter barrel - there will be an update in a later post.