From the Inbox (and Outbox)

I receive a stready stream of emails about the site, some of which I expand into stand-alone articles (eg Going Green in Newcastle-Upon-Tyne and Solar PV in Diffuse (Cloudy) Daylight) and others of which I follow up privately. Also, I've sent unbidden an email or two to register an opinion...

Below you will find some other interesting brief interchanges (edited as necessary); I hope that you find them useful.

True UK Grid CO2 Intensity (kgCO2/kWh)

Paul Street of the London Development Agency wrote 2008/11/21 to point out:

You reference 0.43kgCO2/kWh (from Defra). This is the governments aspirational long-term target for grid carbon factor. And has little basis behind it. It would be better to use the Defra 3 year rolling average figure (currently 0.52kgCO2/kWh) which is far more representative of the current grid factor. Of course we all hope the grid factor will go down to 0.43 and beyond one day.

Generation at Existing Historic Tidal Mill Sites?

Tidal generation might be a very useful source of electricity for the UK, in part because it is predictable long in advance (unlike wind for example) even if still not (fully) 'demand callable' like fossil fuel generation. Having seen an item about Thorrington tide mill in Essex I wrote to Essex County Council 2008/11/09 asking if it had considered generating electricity and if that would indeed be possible without damage, etc.

Geoffrey Wood (Mills Support Officer) kindly wrote back as follows:

Your query referenc[ing] the possibility of generating electricity at the mill is one we are often asked. The short answer is that we have no plans to pursue the idea based on several factors.

The mill pond is fresh water from Tenpenny Brook and is used for irrigation of crops.

The tide gate is permanently closed to prevent saline water entering the pond and polluting the fresh water.

Water is used from the mill pond to demonstrate the working of the waterwheel very sparingly; the majority of the mill pond is for irrigation.

Models have demonstrated that the present existing machinery would have a very short life and would require constant hourly maintenance and repair.

The economics of producing electricity are just not practical using a 19th century machine with 21st century technology.

Thanks for asking the question though.

Letter to Mr Miliband at DECC

Ed Miliband has been made minister at the new UK Department for Energy and Climate Change, whose mere existence signals the connection between our energy use and what it is probably doing to the planet.

I sent him the following email 2008/10/13 entitled "Two Quick Green Actions":

Dear Mr Miliband,

Firstly, I wish you well with your new portfolio: it is a real opportunity to [do] good and you will need a will of iron to make progress in the face of brickbats and mad suggestions for perpetual-motion machines and punitive destruction of Big Oil, etc!

I have two of my own nutty suggestions for you, but I hope that these might be 'low-hanging fruit' that not involve money, only administrative fiat.

1) Ofgem seems rather to have lost the plot as to the benefit of real new build of renewables rather than shuffling certificates around, according to Dale Vince of Ecotricity: http://www.ecotricity.co.uk/news/dale/ofgem-plan-to-outlaw-green-tariffs.html

I have no particular objections to shuffling of certificates as a secondary activity and have worked with energy traders fairly recently, but Ofgem surely is wrong-headed to regard Ecotricity's *50%* renewable generation for their own customers from their own plant as less green than their rivals' shuffled extant power which looks like a sop to the interests of the large providers and not in the customers' or planet's interests. Maybe you could persuade them to revisit their thinking? "You can get much farther with a kind word and a gun than you can with a kind word alone. Al Capone"

2) Instant CO2-emission savings from UK grid generation this (and each) winter without spending money.

The nub of my suggestion is that grid electricity is most likely at its most carbon-intense when the very maximum demand is being serviced in the weekday winter peak 4pm--9pm since probably almost everything that can run has to, however dirty, so use demand control (as was applied by the DNOs at the request of National Grid in May when Sizewell tripped off for example, primarily voltage reduction in distribution) during those peaks to help shift demand away from the peaks and to within the capacity of less-CO2-intense generation.

If this mechanism works it might be an indication that longer-term Dynamic Demand would be a useful CO2-reduction tool as well as its more usual 'grid balancing' and intermittent-generation-friendly behaviour, eg see: http://www.earth.org.uk/note-on-dynamic-demand-value.html

I hope these are of some interest.

Wind Energy Planning

Vicky Portwain wrote 2008/10/21 to say:

I have just set up an independent web-site called www.windenergyplanning.com.

The web-site has the aim of creating a forum where people can gain some further information about renewable energy but also to share their thoughts, actions and experiences, for example - my next post is going to be an interview with a someone who bought his own 6kW turbine and can give details of costs, and payback. It will also provide specialist guides for securing planning permission for renewable energy projects (small to large scale) and talk about wider issues including global politics.

Grid Connect Microhydro in Yorkshire?

On 2008/09/21 D Britton wrote to me asking:

I wonder if you can help! I have an old school house on the side of [a river] in Yorkshire. I make bio fuels, and have a 6kW lister generator that runs on straight recycled veg oil. It also kicks out 12kW of waste heat via the cooling system, which I am going to connect to my central heating & U Floor heating. I am also interested in a water turbine on the river, it's tidal, & quite fast flowing. I have looked at the ampair uw turbine, but it only produces 100watts and is expensive. I had a deal with npowerjuice to buy back exported KWh, but after 2 years of waiting for an export meter, I gave up and changed to Good Energy, who will pay for everything I produce, but will rely on generation meter readings, although they pay 2/3s less. I am struggling to find info on synchronising the genny to the grid though, do you have any advice at all please? Also, I would eventually like to run some PV, and wind, maybe into a battery bank, so I don't need to run the genny over night, do you have any advice on suppliers for switch gear, to switch from 1 supply to the other?

(I have a small steel fabrication business, so knocking any framework together for anything is no problem.)

To which I responded:

You need a special 'grid-tie' [inverter which deals with synchronisation] to export to the grid, pref to the standard G83/1. If you have three-phase power that will help.

For more help on hydro stuff look at http://www.fieldlines.com/ which is fantastic and full of people who do this stuff all the time. Also they have a great IRC channel at irc://irc.anotherpower.com/otherpower

Solar Power Map of London?

I wrote 2008/09 to the (new) mayor of London, asking:

Can we do something like this for London, possibly including solar thermal (and other microgeneration) too, possibly even off-grid systems?

http://sf.solarmap.org/

Ofgem has the data already of course, by power (Wp) and location (address).

and 2008/09/18 I received the (trimmed) response:

Thank you for your email to the Mayor and your idea of creating a solar power map for London. Your email has been passed to the Energy Team and I have been asked to respond on the Mayor's behalf.

The San Francisco solar power map looks like a great way of promoting solar power and possibly other renewable technologies. Thank you for pointing it out. Officers at the GLA have similarly felt a map of renewable energy techonolgies in London would be useful and have in the past sought central government funding to develop this, however due to the existing resource explained below, it was difficult to justify setting up another system. It should be noted that in London solar power makes up only a small percentage of the city's renewable energy potential.

The Department for Business, Enterprise & Regulatory Reform (BERR) currently have a national system of collecting data on renewable energy technologies. This is presented on a map. However small scale renewables fall below the criteria for collection, which means that the renewables in London are not well reflected. Various organisations have in the past tried to persuade BERR to change the way they collect their data to rectify this. Please see the BERR website for more information: www.restats.org.uk/sites_region.htm. You may wish to convey your thoughts to officials at BERR.

Earth Notes: From the Inbox (and Outbox)