Alternate Energy

[Rich]

I thought that that was explained in the post.
At low tide you open the gates, at high tide you close them.

Brian

There is no movement for an hour each at both high and low tides

 

[Rich]

one solution is water heating solar panels
the professionally made ones work at about 70% effeicienty-


the home made ones work at 50% but cost about 1/10 of the cost
photovonic solar panels seem to be a good idea - but effieceny needs to be better and the cost reduced

And if you're lucky you'll get your money back in this country within 20 yrs

 

[GaryPanic]

And if you're lucky you'll get your money back in this country within 20 yrs

Home made water heaters cost about £100 + time to build

payback around 2-4 yearss (depending on usage/weather)
photovonic - 7-10 years depending on location

cornwall payback quicker than say Glasgow

 

[Atomic Shrimp]

I don't know how much they cost (expensive, I suspect), but I understand those vacuum-insulated glass solar water heating tubes are pretty efficient.

Dick Strawbridge used them in his programme It's Not Easy Being Green - as he was unpacking and installing them, for some reason, there was some water inside one of the elements and it scalded him when he tipped it out - even on a damp, overcast day.

Noted, however, that he seemed to have a fairly ample budget for his whole project.

 

[Rich]

Home made water heaters cost about £100 + time to build

payback around 2-4 yearss (depending on usage/weather)

Only of any use in the summer and installation, running costs etc. of commercial systems takes it back to 20yrs

 

[GaryPanic]

I don't know how much they cost (expensive, I suspect), but I understand those vacuum-insulated glass solar water heating tubes are pretty efficient.

Dick Strawbridge used them in his programme It's Not Easy Being Green - as he was unpacking and installing them, for some reason, there was some water inside one of the elements and it scalded him when he tipped it out - even on a damp, overcast day.

Noted, however, that he seemed to have a fairly ample budget for his whole project.

THis programme is back on- but he is revisiting all of the alternative power supplies (check the BBC website /bloom - i think)

gives the payback time /average costs and links to building these things yourself

its on Monday/tuesday - (BBC 2 anyway)


h

 

[Brianwarnock]

It's the other way round.
When the tide is coming in, the gates are opened to allow the tide to enter the Bay. The flow of the tide powers the turbines.
As the tide starts to ebb, the gates are closed to allow the water to flow back to the sea at a specific rate that matches the arrival of the next tide again powering the turbines.

Which I figure means that you open the gates at low tide and close them at high tide, as I stated.

Brian

 

[Brianwarnock]

There is no movement for an hour each at both high and low tides

And your point is?

Brian

 

[namliam]

An hour of no movement = an hour of no energy... Hopefully that can be covered by (huge) batteries or something... Right now I think most energy is 1:1 delivery:demand

 

[Brianwarnock]

Are you , and I guess Rich, saying that exactly the correct amount of energy is produced 100% of the time, never too much, never too little?

Gee that's amazing.

Brian

 

[namliam]

Not exactly... but pretty much yes... They actually need to balance demand vs creation all the time... I cannot find a link or some info online right now, but I have this piece of trivia in my mind, probably from some news fact or documentary somewhere...

Tidal power though is not without its own potential problems, re: Wiki:
http://en.wikipedia.org/wiki/Tidal_power
Potentially slowing the earths rotation , in say a million years...
But more seriously,
- fish migration
- water exchange (eco system problems with salt water vs fresh water)
- Sedimental exchange (sands and stuff beeing carried by the water)
among surely some other stuff.

 

[Atomic Shrimp]

If that were the case, and supply were able to be adapted promptly to demand, then dropping sporadic alternative energy plants into the grid simply isn't a problem - the adaptive parts of the grid can take it easy (saving fuel) when the windmills, tides and waves are producing, and they can ramp back up when the alternative sources are becalmed.

I'm just not getting the conclusion of the arguments about them not working all the time - help me out: Some alternative energy plans don't produce power all the time, therefore...

 

[Atomic Shrimp]

The ecological impacts you mention are a serious concern - I think there have already been species extinctions partly due to the construction of hydroelectric dams (the Chinese river dolphin?) - tidal dams would run the same risks.

 

[GaryPanic]

If that were the case, and supply were able to be adapted promptly to demand, then dropping sporadic alternative energy plants into the grid simply isn't a problem - the adaptive parts of the grid can take it easy (saving fuel) when the windmills, tides and waves are producing, and they can ramp back up when the alternative sources are becalmed.

I'm just not getting the conclusion of the arguments about them not working all the time - help me out: Some alternative energy plans don't produce power all the time, therefore...

Thats not quite the whole picture


We cannot rely just on eco -

what is required is energy that can be off and on-able

wind is not reliant enough
wave is not relient enough

however these can take the edge off wind can produce around 10-17.5 % or so
Wave energy simliar if not more so you have at least 20% of the energy problem solved on a national basis - now we if we all went eco reduced our energy consumtion that we might stand a chance - but we would still need
Nuclear
coal or other burning fuel (such as rubbish/-Garbage for our stateside cousins)
Gas .


There are some clever people out there working on alternatives - hopefully getting all in place in time

Hydrogen cars seem a good idea - but a decent public transport system (and affordable one please) would really help out

 

[Rich]

And your point is?

Brian

My point is as was asked, what happens when the tide is out for an hour at low tide and in for an hour at high tide?

 

[Rich]

Are you , and I guess Rich, saying that exactly the correct amount of energy is produced 100% of the time, never too much, never too little?

Gee that's amazing.

Brian

Where?

 

[Atomic Shrimp]

We cannot rely just on eco -

I agree - but that's my point - I haven't seen anyone arguing that we should. There's a difference between doing it and throwing everything else away and relying on it.

One thing that might also help - but I haven't seen anything much written on it - is sort of like the old Economy 7 idea, but more flexible - there are probably quite a lot of demands out there for power that are not very time-specific - for example, I'd be happy to let my washing machine decide when, in the next 24 hours, was the best (and most economical) time to start washing a load.
Communication and networking is cheap and easy now, so this sort of thing could probably be managed in a much smarter adaptive way than just rigidly defining 'peak' and 'off peak' time periods, as is/was the case with Economy 7.
A properly balanced system of billing premiums could perhaps encourage a certain portion of the demand to become more time-flexible, matching supply more closely.

Obviously wouldn't work for everything, or even most things, but I think it would work enough to be worthwhile.

 

[Atomic Shrimp]

My point is as was asked, what happens when the tide is out for an hour at low tide and in for an hour at high tide?

We use eggs from a different basket - including conventional power generation methods as necessary.

It's also worth noting that by its very nature, the tide isn't the same the world over - for example, at the exact time of writing this, the tide here in Portsmouth is at peak, about 4.7 metres. In Weymouth, just 60 miles away, the tide is the complete opposite - at the low ebb, 0.36m, so a decent distribution system could quite possibly iron out a lot of the bumps.

 

[Rich]

Here's the local reaction to a plan to build a huge wind turbine to power a tourist attraction

http://www.cornwall24.co.uk/module-pnForum-viewtopic-topic-3992.htm

 

[Rich]

We use eggs from a different basket - including conventional power generation methods as necessary.

It's also worth noting that by its very nature, the tide isn't the same the world over - for example, at the exact time of writing this, the tide here in Portsmouth is at peak, about 4.7 metres. In Weymouth, just 60 miles away, the tide is the complete opposite - at the low ebb, 0.36m, so a decent distribution system could quite possibly iron out a lot of the bumps.

Yes I'm aware of that, but the example cited was for just one tidal flow, we are at an advantage in the UK because of the coastline however the cost of building and running these things and the fact that the output cannot easily be increased to meet demand means that like wind turbines the aren't going to save the planet, wave power at this minute seems far more feasible