Green & Ethical Investment News and Suggestions

Coastalwatch

Coastalwatch said:

FTSE made positive progress this week finishing at 6915, the closest it's been to the 7k mark since the crash last year. Thankfully our ISA followed the trend also showing close to a ten percent increase for its duration. So approx 2.5% per annum, which coincidentally, was the favourite figure our maths teacher used to come up with when setting simple and compound interest questions back in the early sixties. Strange how some seemingly insignificant facts stay etched in the memory bank.

Green Energy Storage fund has prospered also finishing 14% up.

With utility investments considered safe havens at times of financial turmoil but outpaced when it comes to long term growth the GESF appears to be bucking the trend for now.

Early days as yet I guess!

Just a week late and dear FTSE finally closed above 7k at 7019.53. Our ISA reflected this with a half % rise so just clearing 10% since inception. While it's prospered well in the last year I had thought it might overhaul the Green Energy Storage Fund by now. In fact that finished the week 2% up totalling 16% so stretching further ahead.

Coastalwatch

Following a brief flirtation above the 7k mark FTSE spent the next two weeks below it until this week when it finished at 7129.71. In spite of having another management fee taken the ISA held up just above 10% while the Green Energy storage fund put on spurt to close 17.5% ahead. Probably due to the imminent arrival of another dividend payout in June!

Coastalwatch

Just a heads up for those interested with investing in Cornish Lithium, the start up company seeking to mine and produce Lithium for the UK EV car industry in an environmentally sustainable manner, that they are planning a second crowdfunding raise shortly on Crowdcube.

Not a recommendation, but as it did sell out quickly at the last raise anyone interested might wish to commence any due diligence etc prior to the event.

Exiled_Tyke

I see Gravitricity has been crowd funding on Crowdcube (I'm guessing you all know this and I'm late the party) and that it closes today.  I was very sceptical about their idea but reading through their proposal I'm now intrigued as to whether this really could be viable.  I know this also has been mentioned on other threads so apologies if I'm merely repeating what is already known.  A number of stats stand out for me - they've used 25 tonne weights to generate 125 KkW.  A 15m tower produces electricity for 10 seconds which I suppose is the disappointing statistic.  They reckon there are 101 available 200m unfilled shafts in the UK.  

It will be very interesting to see if this is ever financially viable for electricity storage. 

QrizB

Exiled_Tyke said:

A number of stats stand out for me - they've used 25 tonne weights to generate 125 kW.  A 15m tower produces electricity for 10 seconds which I suppose is the disappointing statistic.  They reckon there are 101 available 200m unfilled shafts in the UK.  
It will be very interesting to see if this is ever financially viable for electricity storage. 

Gravitational potential energy is simply mgh - mass x "g" x height. 25 tonnes at 15 metres has a potential energy of (25,000 x 9.81 x 15 = ) 3.68 megajoules. If they're getting 125kW for 10 seconds back out, that's 1.25 megajoules. Their generator is 29% efficient.

I don't know how efficient their motor is at lifting the 25 tonne weight in the first place but even if it's perfect, an overall energy balance of 29% isn't great (battery storage, for example, is something like 80% efficient, almost 3 times better).

If thyey use 100 mineshafts, each 200m deep, and scale up from a 25 tonne weight to a 250 tonne weight and 125kW generator to 1.1MW, the stored energy will be (100 x 200,000 x 9.81 x 200 about 40 gigajoules and at 29% efficiency could supply 11.4 gigajoules - 110 megawatts for 114 seconds (almost 2 minutes).

For comparison the Dinorwig pumped storage hydro plant stores 33 terajoules (33,000 gigajoules).

Exiled_Tyke

QrizB said:

Exiled_Tyke said:

A number of stats stand out for me - they've used 25 tonne weights to generate 125 kW.  A 15m tower produces electricity for 10 seconds which I suppose is the disappointing statistic.  They reckon there are 101 available 200m unfilled shafts in the UK.  
It will be very interesting to see if this is ever financially viable for electricity storage. 

Gravitational potential energy is simply mgh - mass x "g" x height. 25 tonnes at 15 metres has a potential energy of (25,000 x 9.81 x 15 3.68 megajoules. If they're getting 125kW for 10 seconds back out, that's 1.25 megajoules. Their generator is 29% efficient.

I don't know how efficient their motor is at lifting the 25 tonne weight in the first place but even if it's perfect, an overall energy balance of 29% isn't great (battery storage, for example, is something like 80% efficient, almost 3 times better).

If thyey use 100 mineshafts, each 200m deep, and scale up from a 25 tonne weight to a 250 tonne weight and 125kW generator to 1.1MW, the stored energy will be (100 x 200,000 x 9.81 x 200 about 40 gigajoules and at 29% efficiency could supply 11.4 gigajoules - 110 megawatts for 114 seconds (almost 2 minutes).

For comparison the Dinorwig pumped storage hydro plant stores 33 terajoules (33,000 gigajoules).

Interesting.. Their figures are from a 'demonstrator', I suppose to prove that the concept can work. In which case I'm guessing that they are currently limiting it's operations as they are claiming 80-90% efficiency.  

Reed_Richards

Surely the problem with dropping solid weights down a mine shaft is that the size (and thus mass) of the weight is limited by the width of the shaft.  Whereas if you use liquid weights (i.e. water) you can have a big tank at the bottom and a big tank at the top yet still drop your weight down a narrow shaft.  So you vastly improve the storage capacity by re-inventing the pumped storage hydro plant.  If you replaced the water with a heavier liquid like mercury you could store even more energy, although that would present some other issues.

Coastalwatch

Dynamo Taxi, a company that is producing the first fully electric London black cab is currently looking to raise funds via the Seedrs crowdfunding website.

They have produced 100 of these emission free vehicles to date and seek investment to assist in replacing a portion of the nearly 70,000 FF versions throughout the country over the next ten years.

Can't wait to see this happen as it infuriates me when passing taxi ranks with a good percentage of vehicles idling and polluting the air we breathe!

Martyn1981

Exiled_Tyke said:

I see Gravitricity has been crowd funding on Crowdcube (I'm guessing you all know this and I'm late the party) and that it closes today.  I was very sceptical about their idea but reading through their proposal I'm now intrigued as to whether this really could be viable.  I know this also has been mentioned on other threads so apologies if I'm merely repeating what is already known.  A number of stats stand out for me - they've used 25 tonne weights to generate 125 KkW.  A 15m tower produces electricity for 10 seconds which I suppose is the disappointing statistic.  They reckon there are 101 available 200m unfilled shafts in the UK.  

It will be very interesting to see if this is ever financially viable for electricity storage. 

I may be wrong, but I think the 125kW, 10s test, was with half the weights, as the test rig was a twin weight, 250kW set up. Also that was to demonstrate their ability to offer frequency support by responding within 1s and over a short period.
Their plans are for vastly heavier systems offering MW's of supply for mins to hours, and at around 80-90% efficiency, but most importantly, at a much lower cost per MWh than conventional batteries.
It's a shame the navitron forum has closed, as one of the founders was a member on there.
Looks like loads of potential (energy ;-)), just have to hope it all works on a larger scale.

Exiled_Tyke

Martyn1981 said:

Exiled_Tyke said:

I see Gravitricity has been crowd funding on Crowdcube (I'm guessing you all know this and I'm late the party) and that it closes today.  I was very sceptical about their idea but reading through their proposal I'm now intrigued as to whether this really could be viable.  I know this also has been mentioned on other threads so apologies if I'm merely repeating what is already known.  A number of stats stand out for me - they've used 25 tonne weights to generate 125 KkW.  A 15m tower produces electricity for 10 seconds which I suppose is the disappointing statistic.  They reckon there are 101 available 200m unfilled shafts in the UK.  

It will be very interesting to see if this is ever financially viable for electricity storage. 

I may be wrong, but I think the 125kW, 10s test, was with half the weights, as the test rig was a twin weight, 250kW set up. Also that was to demonstrate their ability to offer frequency support by responding within 1s and over a short period.
Their plans are for vastly heavier systems offering MW's of supply for mins to hours, and at around 80-90% efficiency, but most importantly, at a much lower cost per MWh than conventional batteries.
It's a shame the navitron forum has closed, as one of the founders was a member on there.
Looks like loads of potential (energy ;-)), just have to hope it all works on a larger scale.

I'm not sure I can forgive you for the terrible pun!