Rainwater Harvesting

Rainwater can be harnessed to water plants or can be cleaned on site and used as greywater (flushing toilets and washing clothes).

WATERING PLANTS
We've used second-hand Intermediate Bulk Containers (IBCs) which can be picked up for about £20. As much as 2000L can be collected in a couple of hours of heavy rain (admittedly we have a large roof of ...). We pump the water into another IBC in a trailer with a small 12v pump and drive round the field watering acres of trees
As with most things, building a simple DIY contraption costs more than you'd probably think, with the IBCs, pump, various bit of pipes it came to about £200. But with water costing on average £2/1000 litres, it should pay for itself in a couple of years with acres of trees to water.

We use 1000 Litre IBCs for rainwater storage, they only cost about £20

RAINWATER FOR GREY-WATER

...Keep posted....

Fruit, Veg' and Woodland

FRUIT ORCHARD



VEGETABLE PATCH



WOODLAND
We need a couple of acres of woodland for the Bird On The Hand falconry centre to be run on the site. In May 2010 we planted 2 acres of poplar (500 trees).
Poplar are fast growing and good for screens (we have also planted a boundary around the plot). The poplar will quickly establish a woodland, and we will be gradually inter-plant with other species, the poplar will provide shelter for less hardy species.

Poplar are fast growing, we will inter-plant them with other species

Growing Biomass..

With about 8 acres of grassland to play with, we will grow our own biomass for a heating system. We will grow the crop, harvest it, dry it and burn it in a biomass boiler. This energy will heat water used for the central heating.

HYBRID WILLOW TREES
Hybrid willow trees are often used as biomass due to their fast growing nature. They grow up to 2 metres per year, and in four years (at time for harvest) they should be about 6-7 metres.

OUR PLANTING
We aim to plant 2 acres of hybrid willow (9000 trees) which should cover our heating requirements. It will be a four year rotational crop, with a quarter harvested each year and a year to let them dry.

In March 2011 we planted 4600 cuttings (a rootless stick which will self root) over a one acre plot. We have planted 1 foot cuttings (only 5cm is showing above ground). Next year we will take one cutting from each tree and plant another acre of 4600 trees (instead of buying all 9000 trees now)

We have used woven plastic sheet to keep the weeds down but we haven't used rabbit guards (we have accepted that some, but not a large amount, we be eaten by rabbits.)

THE YIELD....
...Keep posted...

PV Panel Options...

We believe we need need 23 panels of 210 watts, making a  ..................Following the basic criteria that the PV panels should face south, not be shaded and not too far from the house to reduce transmission losses, the two best locations would be on the shed or on the barn.

The shed or the barn are the main options for the location PV panels

LOCATION OF PANELS


This table shows the pros and cons of the locations. Generally the optimum angle for PV panels is about 30 degrees to the horizontal but 'Angle of Panels' (below) explains why we are considering vertical panels.

The pros and cons of the different panel locations

The best position will be ‘vertical on barn’ depending on:

-  The angle to horizontal (90 degrees) receiving enough daylight.

 - Not being shaded by the house.

ANGLE OF PANELS (On barn roof vs. Vertical on barn)

Using the software on PVGIS I compared the electricity production for the different positions of the PV panels. The amount of electricity required per day is around 5kWh throughout the year (as shown by the red line). The graphs show that the roof PV panels produce more electricity throughout the year compared to vertical PV panels. However, the vertical panels take better advantage of the low winter sun, when we are short of electricity, while still producing enough electricity in summer.

Graphs to show that vertical panels will be preferable to panels at 15 degrees

SHADING ON PANELS

The drawings below show potential shading on the panels. It can be seen in late September there is no shading on panels. In late November the panels start to be shaded in late afternoon. However, how much electricity are the panels going to be producing after 3pm in the winter even if not shaded?

Our initial thought is that the benefit of ease of installation outweighs the minimal loss of electricity production for an hour a day in the winter months.

Shading the on the panels at different times of the year and throughout the day

Where To Get Electricity??

The barn is not connected to mains electricty at the minute and we have been given an estimate of £25,000 to connect. With electricity prices on the increase and the government giving feed-in tariffs for renewable electricity, it seems being off-grid may be the best option.

THE OPTIONS
Wind turbine

Solar Photovoltaic

Water..?

OUR CHOICE
We have chosen to go with PV panels. We a a huge south facing roof and it's not a particulary windy area (we could get a ...wind test, but this would be at an expense and PV seems.....

Which Heating System?

We are currently not connected to mains gas or electricity, thersfore deciding how to heat the house and water is an exciting and big decision. As oil and gas are becoming ever more expensive we are considering the 'green' options.

THE OPTIONS...

Biomass: Biomass is biological matter e.g. wood, straw, poultry litter. Biomass is put into a boiler and burnt to produce energy to heat water which can be used for radiators/underfloor heating. The most common form for a biomass boiler is wood chips, pellets or logs.

Wood from a sustainable source is carbon neutral, the since the CO₂ produced when burned is equal to the amount the tree absorbed in its lifetime.

Ground source heat pump (GSHP): A pump works by using a vapour compression cycle, just like a fridge. It uses low grade heat, normally from underground, and concentrates it to a temperature where it can be used it heat radiators and water supply. It requires relatively little electricity to do this, just take to circulate the refrigerant. For instance a GSHP can provide 4kW of heating for just 1KW of electricity. 

GSHPs use a coil of pipe under ground which extracts the heat from the earth. The pipe is usually about 100m long and 1-2m underground. A vertical loop up to 100m deep can be used if the plot of land available is small.

Wood Burning Stoves: Wood burning stoves are a sustainable and aesthetically pleasing addition to heating a home, generally providing space heating one room and the possibility of cooking.

Solar hot water panels: Solar panels (not to be confused with photovoltaic panels) consist of tubes of heat transfer liquid which the sun heats up and then is pumped to a coil within the house’s hot water cylinder.

DIY solar panels can be relatively easy to build and are reasonably efficient.

WHICH SYSTEM FOR US?

We have chosen to use a biomass boiler for to heat the whole house and water for the following reasons:

•          We have to the land to produce our own crop. Willow crop can grow in just 4 years (website link). We need to plant, harvest and dry the crop before use.
•          GSHP will require electricity (up to ...kWH). As all electricity will be produced on site, we would need to increase our number of photovoltaic panels and which is expensive. The most heat is needed in the winter, which is when the PV panels are producing the least electricity, hence being two conflicting technologies for off-grid properties.
•          For GSHP to be most effective the house should be extremely well insulated. In our building insulation is not ideal, the walls are solid (not cavity) and the rooms are not large enough to accommodate extremely good (thick) insulation.
•         Solar panels are an additional expense and complication that we don’t feel is necessary. It will be easier and have a smaller capital cost to equal any potential heat gain from the sun by harvesting and burning a few extra trees.

WHICH BIOMASS BOILER?

... Stay posted ...

GOVERNMENT INCENTIVES...

Renewable Heat Incentive (RHI)

As part of the ‘Renewable Heat Incentive’ scheme the Government will pay individuals who use renewable technologies for heating.

For example, for our 45kW biomass boiler, the Government will pay us 9 pence per kWh of energy we produce. If we were to use 15,000kWh of energy per year this would amount to the Government paying us £1350 per year for the next 15 years, plus we would have no heating bills. Obviously, the initial the capital cost of the biomass boiler and cost of growing, harvesting and drying the logs need to be taken into account.

The Government have said that the scheme will go ahead in June 2011, but the tariffs are yet to be finalised. A similar scheme for photovoltaic panels is already in existence.

http://www.rhincentive.co.uk

Energy Saving Trust / Woodland trust??? also provide grants for planting trees...??? 

Project Background

My family have bought a dilapidated red-brick barn and ten acres of land. The barn has not been lived in for over 100 years; it is not watertight; it is not structurally sound; and does not have electricity or sewage connection. It does have planning permission to be converted for residential use.

Over the next year or so is I will be designing and re-building the barn economically. With government feed-in tariffs for renewable energy and the rising price of oil, it is probable a lot of design will be ‘green’.

The property will also be used for the Bird On The Hand falconry centre, requiring woodland, aviaries and a visitor centre.

I hope you will keep posted and watch my knowledge of sustainable engineering grow and the project unfold.

Bird's eye view of the ten acre plot

Drawing showing use of land