Solar Panel Guide Discussion

Martyn1981

LittleVermin wrote: »

Severn Barrage - oh, NO thank you! The construction industry was just salivating a couple of years back when the Severn Barrage came back up the agenda. All that lovely concrete!

But also all those mucked up habitats, etc, etc. There were some smarter suggestions for split tidal 'ponds'. But why not just use tidal currents? Lunar power. Predictable. By having several generators in different places the output is evened out, though birds' feet will still get warmed during transmission.

There are several pilots in operation. And a large socket offshore near St Ives: this "Wave Hub" has nothing plugged into it yet.

(Apologies for the title of this post - couldn't resist it!).

..

Big project, big bucks, and very big amounts of concrete yes, but look at the potential. Number 1 of top 20 list of tidal schemes in the UK, and larger than all the other 19 added together.

The ponds are cheaper and simpler, but less powerful. Tidal currents brilliant, but again tiny amount of generation compared to trapping that vast amount of water.

I appreciate the environmental concerns, these have split many organisations, I think the ex-head of FoE is pro, whilst new head is anti. Trying to balance destruction of environment in the area against helping the wider environment - ouch, headache time. Is the defence that the birds living on the mud-flats are not endangered valid, or a cop-out?

The main issue, as always, has got to be money. Admit to not knowing the full story, but my understanding is that the government applied the maximum future multiplier to the Barrage costs for estimating purposes, yet applied one of the lowest to the (then) planned nuclear programme (approx 10 plants, across 3 to 5 sites). Obviously recent news suggests that the nuclear cost estimates may have been a little generous.

The result is that Barrage generation costs currently sit above on-shore wind, and predicted off-shore wind (as prices are still falling). Till the numbers add up, I doubt anything is going to happen one way or another.

(Title - loved it! Are we playing the same game, or have I gone off on a tangent?)

Mart.

John_Pierpoint

We often see these arguments presented as engineers versus economists.
Much of the problem is politics.
There are some things that cannot be said and some things that cannot be done (openly) by a political system with a 5 year time horizon. [We have a moderately powerful Civil Service - does it have a secret core that keeps projects alive during periods of political change?]

For example we had a "Department of Transport" and a loss making nationalised Railway. So in reality we had a department of roads.
Similarly we had a nationalised electricity and coal industry. How exactly could the managers of those industries progress their careers by mining less coal and producing less electricity? Where was the requirement to produce hot water? Then there was the decision to be made: Is it more efficient to take the coal to the people and create heat and power or to burn the coal at the mine, saving all that investment in transport but at a cost of wasting a significant amount of heat and electricity?
It is an unsustainable model, all mines are be definition temporary.
The politicians want bombs fast. It is a dangerous technology with a a legacy of pollution for thousands of future generations. The USSR wrote off inland areas of their empire.
http://www.logtv.com/films/chelyabinsk/
In this crowded island we put the "power stations" in remote coastal locations for easy disposal of "low intensity" waste. We have only had one "near miss" in the nuclear accident stakes, thanks to a "nutty" insistence on fitting the "chimneys" of Windscale with filters
http://en.wikipedia.org/wiki/Sellafield]

Then the economics were again upset by the discovery of cheap North Sea gas, enabling low capital cost and flexible generation.

Now we have two powerful "drivers" - competition for resources boosting prices and greenhouse gasses poisoning the planet.
We also have a world trying to make rational economic decisions using two very unreliable accounting units of measurement: Carbon credits and massive deficit fiat currency.

Meanwhile on the political front we have an electorate, where a minority intellectually understand the scarce resource argument, an even smaller minority intellectually accept and understand the implications of climate change and a vanishingly small minority demonstrate in their daily life, that they are prepared to do anything about it.

In the final analysis, where there is a political will, there will be political action, almost in spite of the economics; when there is not a political will the issues get "kicked down the road" for a future generation.

London Olympics 2011 is a fine example of the former; redesigning the UK's power systems is already showing the legacy of the latter.



Iconic image of an economic model where coal was delivered to a city centre power plant, using low cost water transport. A plant with some CHP output.

orrery

LittleVermin wrote: »

A little unfair to (for example) Friends of the Earth which has been arguing for Combined Heat & Power for over 30 years, I believe!

The reviews I've seen indicate that combined heat and power makes no sense, as you then fail to optimise either. It makes more sense to split the two and then optimise each part. This then leads to the question .. why are you building a heat station anyway? People can produce heat so very easily, efficiently, more locally and more controllably.

The only sensible thing to do with the heat is to recover it and use it for further power generation - a decision which can be made on the economy of the process itself.

John_Pierpoint

I think the answer to that question is that with modern technology, you are getting 35% + of the heat as a "free" by-product of the electrical power production, it seems like waste to bung it into the river. I have never heard of a hot water turbine.

I think the Danes got it right:
Live in town in a flat: Piped heat from the CHP plant.
Live in the suburbs in a house: Condensing gas boiler
Live in the countryside off gas grid: Ground source heat pump & under floor heating.

Here is another iconic picture for me - it is Kingston upon Thames former power station and baby brother of Battersea. That crane was probably building a replacement "luxury" block of flats to replace the former coal grab. The grab came swinging through a building built over the riverside road and then dropped to get the coal from barges on the river.

Aged about 6, I can remember my mother explaining the power station made (scary) electricity. I asked her why there was hot steaming water dripping over slats on the other side if the road (I had probably been threatened with deportation for leaving the hot tap running - but mum could not explain the hypocrisy). I was a 12 year old before I realised that all the winter fishermen congregated round the outfall, just down stream from the coal grab, because the fish did too.

Anyone want to finance a dredging of the river and a reverse panning of the result - they dropped plenty of coal in the water and while crossing the road - great fun.



This new proposal for a replacement power station at Kingston, brings this discussion round in a circle - in that it compares the above scr3ws with PV panels.
http://protonsforbreakfast.wordpress.com/category/simple-science/page/5/
(It is the second item on the page)

orrery

John_Pierpoint wrote: »

Here is another iconic picture for me - it is Kingston upon Thames former power station and baby brother of Battersea.

What you've illustrated is exactly (in an updated form) what is being built on Bedford river as we speak.

John_Pierpoint

Got a link ?

France has lots of little hydro installations on most weirs, but they are unusually shrouded by corrugated iron (perhaps for safety reasons).

orrery

John_Pierpoint wrote: »

Got a link ?

An old one:
http://www.bbc.co.uk/news/uk-england-beds-bucks-herts-14667789
Luckily it is now well underway, with two concrete half-cylinders in place.
http://www.bedford.gov.uk/council_and_democracy/council_news/archived_news/april_2010/ancientgreece_to_power_bedford.aspx

HalloweenJack

everyone wants renewables just NOT IN MY BACKYARD!

and so schemes get stopped - what will happen when the lights go out with brown outs.....

grahamc2003

HalloweenJack wrote: »

everyone wants renewables just NOT IN MY BACKYARD!

and so schemes get stopped - what will happen when the lights go out with brown outs.....

I think when the lights go out in 4 or 5 years time when more large stations reach the end of their lives, peoples' minds will finally be well and truly focused on the underlying issues. I expect initially many will be utterly confused at to why there is an insufficient supply of electricity to meet demand at certain times when we, as a country, have spent billions on wind and solar which, in general, the puiblic have been told are the very technologies we need to keep the lights on.

Currently there is a massive gas building program going on - about 3GW of small station gas capacity has gone in in the last year (...and people wonder why bills are on the rise) - so much for energy security, co2 free energy, and many other of the arguments put forward when, behind the scenes, the walk is very different from the talk.

Of course, electricity is critical in developed countries - the economy is dependent on it and, belatedly, someone in the government has, almost in panic imv, encouraged a massive gas build as the only short term (but very expensive and strategically wrong) option to minimise the electricity rationing.

A dose of realism will enter the public domain when they have to manage with no electricity certain times of the day, and then the government will be forced to take on board the views of energy industry experts instead of the current drivers of energy policy. I expect at that point, the new Nuclear program (as the single realistic option for the substantive UK generation) often discussed at that level will finally commence and not allowed to be derailed. I also expect a new Nuclear program to be administered and invested in by government - the whole area in the UK being too costly and with too high a political risk for any private or public company.

ronlizpatsimon

There has been some recent references concerning loss of power along the overhead cables.
No doubt this is true. However; I would suggest the loss is minimal. Consider wintry weather. Often power lines fall down due to the additional weight of ice sticking to the cables. If they are slightly warm; the ice would not stick.