A summer of generation and consumption

At the holiday house (www.VarisHoliday.co.uk), we now have about three months data (96 days).    The house has had guest in for most of this time but we ran the heating regardless as we wanted to bring the house which had sat with minimal heating through the winter up to proper warmth throughout.

From 5th May to 9th August:

Total house import                            1066 kWh
PV Generation                                  1073 kWh
Air source heat pump consumption  1082 kWh

So on average, 11kWh a day for each measure.  

We've experimented with the setting on the ASHP so that it runs more during the day so we maximise running the ASHP on sunshine. 

Generation, consumption and import

We have just had the first full year where we've had PV panels and monitoring of our energy consumption.  We have also been sad enough to take daily readings of generation and import.

So for other energy anoraks out there (showing 7 day moving averages to get rid of the 'noise'):

The captions are a little difficult to read, but you see that Consumption (green) generally sticks in the 10-15kWh/day with dips when we are on away, import (red) seems to have a baseline of 5kWh/day in summer, rising to 10kWh (or more) in winter and that the PV panels (blue) are more or less performing as we expected (dark blue). 

The electricity bills have more-or-less halved as a result of the PV panels.

Annual figures come out at: 
PV Generation 2856 kWh
Import 2505 kWh
Consumption 3913 kWh 
... and therefore we estimate Export at 1447 kWh.  


We are pretty focused on running the washing machine and the dishwasher when the sun shines (or at least during the day) but it's diffcult to time-shift much of our other consumption.

You can see an overnight cycle which is fridge/freezer.  The peaks are the cooking and kettle and then we have computers and TVs.

The apparent base load is getting our attention but the honest calculation is that moving to more energy efficient appliances but it's not worth us making a special effort so we will think about this as we need to replace   The induction hob however does seem to be efficient (all our cooking is electric).  We do have a few gizmos to help ensure that we don't leave things on standby. 

So, what we really need is cost effective ways to store our electricty to use it later (see previous post below) - and focus on using less oil for water and space heating.  The woodburning stove is great for cold days and we have ready supplies of wood - but I think tackling the insulation of our solid walls is the next serious investment.   


Thanks to the Macauley (now James Hutton) Institute for the Consumption Monitoring kit.
 

Energy use and Generation

A recent report from UKERC The UK energy system in 2050:Comparing Low-Carbon, Resilient Scenarios highlights a few important challenges we all have to face.  These are a selection of the main 'pull out' quotes from the report (my bold)

• ... the sets of technologies to meet the challenge exist, and deploying them is a much lower cost option than the damages from climate change, estimates elsewhere that will ensue if the UK and other countries fail to rise to it.
• .. of the ways in which the Elastic Demand version of MARKEL (the model used) can meet policy objectives (e.g. carbon reduction constraints) is to reduce energy service demands through price elasticities of demand. 
• Hydrogen and electric vehicles dominate the transport mix by 2050, this has resultant impacts on the power sector with vehicles being recharged during time of low demand
• For the targets to be met an economy wide carbon price would need to be gradually imposed, on top of all existing carbpon.enery taxes, reaching about the current level of fuel duty by 2050.
• All buildings, new and existing, will have to be much more energy efficient.

With the ppm of CO2 in our atmosphere tripping over the 400 mark for the first time and China now announcing serious carbon emission reduction targets, we have a two choices:
bury our heads in the sand or take action.

Energy Monitoring

I have joined the Macauley Land Use Research Institute's North East Scotland Energy Monitoring Project.  They have provided one of those nifty little devices that display current energy use and the kit to link this to the internet so that a continuous track of our electricity use and house temperature is displayed.

Part of the intent of the research is to see how energy feedback measures help households monitor and manage their energy.  I am sure the effect will wear off, but we have already learnt just how much energy different devices around the house use.  And Gordon has started to fill the kettle only half way and switch off lights.  

Meanwhile we will keep on visiting the on-line trace, slightly fascinated by the data.

Energy Controversies

Thanks to the (anonymous) commenter who pointed me to the University of Aberdeen's lecture series Energy Controversies.

http://energycontroversies.abdn.ac.uk/

Just how serious is Climate Change. ... or should that be catastrophe?

It takes a while for politicians to catch up with science. And maybe we are too late to avert climate catastrophe (see http://www.guardian.co.uk/commentisfree/2009/mar/12/climate-change-copenhagen-monbiot

Now the Maldives, most of which is just 1.5m above sea level have announced that they plan (that's plan not aim) to be carbon neutral in just 10 years.

OK, they have a great incentive to make progress on this. There is a real risk that their country will no longer exist by the end of the century if the worst predictions come true.

But the cost for the package of low-carbon measures is estimated to be about $110m a year for 10 years. The scheme should pay for itself quite quickly, because the Maldives will no longer need to import oil products for electricity generation, transport and other functions. If the oil price were to rise to $100 per barrel, the payback period would be as short as 11 years. At current prices, it would take roughly twice as long to break even.

President of the Maldives, Mohamed Nasheed said: "Climate change is a global emergency. The world is in danger of going into cardiac arrest, yet we behave as if we've caught a common cold. Today, the Maldives has announced plans to become the world's most eco-friendly country. I can only hope other nations follow suit."

See full story at http://www.guardian.co.uk/environment/2009/mar/15/maldives-president-nasheed-carbon-neutral

Washing machines

My washing machine is broken - it's the pump that empties the water. It's 15 years old so I've bought a new one. The ratings for energy efficiency are a bit odd.

I've gone for an A+AA machine and the manufacturer tells me that the energy consumption is 1.02 kwh/cycle and Water consumption is 45 litres/cycle-wash.

But I've seen an AAC machine that quotes 49 litres normal water consumption for a 60 degree wash and 0.95kW energy consumption per cycle.

Both machines take a 6kg load.

So have I been suckered by the labelling?