Cyprus-Forum.com

[devil]

regarding Solar Panels. With storage Batteries charged all day long, and converters from a DC to AC, for domestic usage, one should be able to subsides most of their energy needs, with the normal power grid being there, to pick up the slack, when needed. Sure the initial investment will be high, but so is a Nuclear Power Plant.

Let's do some arithmetic with rounded figures to see whether you're right.

The present production capacity in the RoC is ~1 GW, but we shall need to double this by 2015. The best we can do with a PV panel at 25°C is about 150 W/m². To produce 2 GW in full noontime sun in spring or autumn would therefore need 13,333,333 m² of panels. Unfortunately, peak demand comes when the temp is > 40°C and the output of the panels drops by ~30% at this temp, so we shall have to up the area to ~20 Mm². This assumes the panels face the sun. However, this assumes we consume electricity for, say, 8 h/day. You suggest batteries to supply the other 16 h, so the actual capacity would have to be tripled to compensate, so we shall need 60 Mm². This assumes the sun shines 365 days per year, which it doesn't. Let's say there are periods of up to 5 days on the trot with no sun. To compensate, we shall have to multiply this, and the battery storage, 5 times. So we shall have to have 300 Mm² of panels. But batteries, over time, have an efficiency which starts at ~80% but drops to 60% after a couple of years and the DC>AC inverter has an efficiency of ~90%. This means that the capacity will now need 550 Mm² of PV panels. This will cover about 8% of the total surface of the Republic.

The current manufacturing cost of solar panels is about €450/m² so, for the panels alone, so we are looking at about €250 billion.

Now, let's look at the batteries. We need these to cover 5 days without sun at, say, 50% of average use (no aircon in winter). 550 Mm² of panels produces 660 MWh in an 8 hour day, so we need half of this as stored energy. A typical car battery is 12 V 50 Ah input, dropping to 30 Ah after a couple of years. This is capable of providing 330 Wh under ideal conditions. We would therefore need a minimum of 1 million such batteries (actually car batteries would be useless, you need special heavy-duty types).

It is difficult to evaluate the total cost of panels plus batteries plus inverters plus changes needed to the grid plus installation costs, but I would say the €500 billion mark would not be very far off the mark. This does not include high costs for maintenance.

Guess what? You could build three (3) EPR nuclear power plants for that, including all the fuel/waste handling, decommissioning costs etc.! And THAT would be three times in excess of our foreseeable needs to 2025!

As for solar thermal power generation, this is even less viable. The problem is you would need about 200 km² of collectors and the heat loss to a central power plant would just not be economical, nor would a multitude of smaller plants.

Solar is fine for small top-ups to a conventional system, but nothing more.

[Kikapu]

regarding Solar Panels. With storage Batteries charged all day long, and converters from a DC to AC, for domestic usage, one should be able to subsides most of their energy needs, with the normal power grid being there, to pick up the slack, when needed. Sure the initial investment will be high, but so is a Nuclear Power Plant.

Let's do some arithmetic with rounded figures to see whether you're right.

The present production capacity in the RoC is ~1 GW, but we shall need to double this by 2015. The best we can do with a PV panel at 25°C is about 150 W/m². To produce 2 GW in full noontime sun in spring or autumn would therefore need 13,333,333 m² of panels. Unfortunately, peak demand comes when the temp is > 40°C and the output of the panels drops by ~30% at this temp, so we shall have to up the area to ~20 Mm². This assumes the panels face the sun. However, this assumes we consume electricity for, say, 8 h/day. You suggest batteries to supply the other 16 h, so the actual capacity would have to be tripled to compensate, so we shall need 60 Mm². This assumes the sun shines 365 days per year, which it doesn't. Let's say there are periods of up to 5 days on the trot with no sun. To compensate, we shall have to multiply this, and the battery storage, 5 times. So we shall have to have 300 Mm² of panels. But batteries, over time, have an efficiency which starts at ~80% but drops to 60% after a couple of years and the DC>AC inverter has an efficiency of ~90%. This means that the capacity will now need 550 Mm² of PV panels. This will cover about 8% of the total surface of the Republic.

The current manufacturing cost of solar panels is about €450/m² so, for the panels alone, so we are looking at about €250 billion.

Now, let's look at the batteries. We need these to cover 5 days without sun at, say, 50% of average use (no aircon in winter). 550 Mm² of panels produces 660 MWh in an 8 hour day, so we need half of this as stored energy. A typical car battery is 12 V 50 Ah input, dropping to 30 Ah after a couple of years. This is capable of providing 330 Wh under ideal conditions. We would therefore need a minimum of 1 million such batteries (actually car batteries would be useless, you need special heavy-duty types).

It is difficult to evaluate the total cost of panels plus batteries plus inverters plus changes needed to the grid plus installation costs, but I would say the €500 billion mark would not be very far off the mark. This does not include high costs for maintenance.

Guess what? You could build three (3) EPR nuclear power plants for that, including all the fuel/waste handling, decommissioning costs etc.! And THAT would be three times in excess of our foreseeable needs to 2025!

As for solar thermal power generation, this is even less viable. The problem is you would need about 200 km² of collectors and the heat loss to a central power plant would just not be economical, nor would a multitude of smaller plants.

Solar is fine for small top-ups to a conventional system, but nothing more.

Thank you for setting me straight Devil.

I had full confidence in you, as always.

GO NUCLEAR POWER:

[GerryWolff]

As for solar thermal power generation, this is even less viable. The problem is you would need about 200 km² of collectors and the heat loss to a central power plant would just not be economical, nor would a multitude of smaller plants.

There is absolutely no need for nuclear power in Cyprus or anywhere else in Europe because there is a simple mature technology that can deliver huge amounts of clean energy without any of the headaches of nuclear power.

I refer to 'concentrating solar power' (CSP), the technique of concentrating sunlight using mirrors to create heat, and then using the heat to raise steam and drive turbines and generators, just like a conventional power station. It is possible to store solar heat in melted salts so that electricity generation may continue through the night or on cloudy days. This technology has been generating electricity successfully in California since 1985 and 100,000 Californian homes are currently powered from this source. CSP plants are now being planned or built in many parts of the world.

CSP works best in hot deserts and, of course, there are not many of these in Europe! But it is feasible and economic to transmit solar electricity over very long distances using highly-efficient 'HVDC' transmission lines. With transmission losses at about 3% per 1000 km, solar electricity may, for example, be transmitted from North Africa to London with less than 10% loss of power. A large-scale HVDC transmission grid has also been proposed by the wind energy company Airtricity as a means of optimising the use of wind power throughout Europe.

Less than 1% of the world's hot deserts could produce as much electricity as the world currently consumes. A recent report from the American Solar Energy Society says that CSP plants in the south western states of the US "could provide nearly 7,000 GW of capacity, or ***about seven times the current total US electric capacity***" (emphasis added). The solar potential in the Middle East and North Africa is at least as great.

In the recent 'TRANS-CSP' report commissioned by the German government, it is estimated that CSP electricity, imported from North Africa and the Middle East, could become one of the cheapest sources of electricity in Europe, including the cost of transmission. That report shows in great detail how Europe can meet all its needs for electricity, make deep cuts in CO2 emissions, and phase out nuclear power at the same time.

Further information about CSP may be found at www.trec-uk.org.uk and www.trecers.net . Copies of the TRANS-CSP report may be downloaded from www.trec-uk.org.uk/reports.htm . The many problems associated with nuclear power are summarised at www.mng.org.uk/gh/no_nukes.htm .

[devil]

Cyprus simply does not have enough land space available for mirror farms. The overall efficiency of CSP is <30% (solar radiation received to electricity), so work it out, as I did above, how many km² of mirror farms would be needed to provide the kWh the country consumes and is estimated will consume by 2015, based on 5 days without sun.

I wouldn't read too many extremist ecopolitical web sites if I were you!!!!

By the way, I'm a Chartered Electrical Engineer, and have been for 53 years, so I do have an inkling of what I'm talking about.

[GerryWolff]

Cyprus simply does not have enough land space available for mirror farms. The overall efficiency of CSP is <30% (solar radiation received to electricity), so work it out, as I did above, how many km² of mirror farms would be needed to provide the kWh the country consumes and is estimated will consume by 2015, based on 5 days without sun.

I wouldn't read too many extremist ecopolitical web sites if I were you!!!!

By the way, I'm a Chartered Electrical Engineer, and have been for 53 years, so I do have an inkling of what I'm talking about.

People often assume that renewable energy must always be local. But there is huge potential in HVDC transmission lines. With transmission losses at about 3% per 1000 km, it is feasible and economic to transmit solar electricity over very long distances.

CSP works best in hot deserts where land is plentiful and cheap. Less than 1% of the world's hot deserts could generate as much electricity as the world currently consumes. 90% of the world's population lives within 2700 km of a hot desert and this is well within the scope of HVDC transmission.

All of these proposals are backed up by two very substantial reports by German engineers - not "extremist ecopolitical web sites" by any stretch of the imagination. Those two reports can be downloaded from http://www.trec-uk.org.uk/reports.htm .

[Kikapu]

I refer to 'concentrating solar power' (CSP), the technique of concentrating sunlight using mirrors to create heat, and then using the heat to raise steam and drive turbines and generators, just like a conventional power station. It is possible to store solar heat in melted salts so that electricity generation may continue through the night or on cloudy days. This technology has been generating electricity successfully in California since 1985 and 100,000 Californian homes are currently powered from this source. CSP plants are now being planned or built in many parts of the world..

GW,

Are you talking about the Solar Panel/ Mirrors on Highway 58 between Mojave and Barstow near Edwards Air Force Base by any chance, in Mojave Desert. I have driven by there many of times, and one could see them from the road. I can't remember exactly how big of Solar Farm it is, but I would guess, it is no larger than one square mile. If that can produce enough power to supply 100,000 homes of all their electrical needs, then there's great hope yet.

[Jerry]

Devil, surely there is enough "waste" land in Cyprus where CSP plants could be built. 200sq km from an island of 9000 sq km should be feasible. As for storing energy for rainy days wouldn't hydro-electric work in Cyprus?

[devil]

I'm not going to get into a 'tiz-tiz not' kind of argument.

Firstly, your trec-uk organisation is an unofficial NGO, clearly with an agenda.

Secondly, you distort facts.
You state, re the Kramer Junction site:

This technology has been generating electricity successfully in California since 1985 and 100,000 Californian homes are currently powered from this source.

Yet the Kramer Junction guys themselves state:

The plants operate on solar driven power, to ensure uninterrupted power during peak demand periods. On cloudy days or early evenings, an auxiliary natural gas-fired heater is available and operates to supplement sources of power.

(my emphases)
It does not supply electricity to 100,000 homes on a 24/7 basis, as you imply. In fact, the NG plant is operated for <25% of the time to qualify for benefits, so that your implication is, I suggest, deliberately intended to mislead.

As for submarine HVDC connections to this island, the distances are too great from North Africa with today's technology, 100 km being about the practical limit. Furthermore, you would need 4 pairs/poles to ensure reliability for 2 GW at, say 350 kV, 500 MW, in 2015, even if it were possible. However, would you rely on Libya or Egypt to supply Cyprus with electricity? We have seen that Russia can drop oil/gas supplies at the drop of a hat. What would happen if a future President offends Ghadafi or Mubarak or their successors? You cannot simply ignore the political implications. At least with LNG, there are multiple sources available: with a cable with a switch at the other end, you have no choice.

Last submission to this thread. My case rests.

[Sotos]

What about solar power with photovoltaic systems? If every building had some solar cells on its roof then most of our needs would be covered

Fine in theory, but
a) who is going to pay for the enormous capital cost (tens of times more than nuke)?
b) who wants to pay for electricity at 35 c/kWh, instead of 6 c/kWh?
c) most people want to watch their TV after the sun goes down and electric light would also be nice.

PV may be OK to reduce the load of aircon on a sunny day. And more than ~20% of peak grid capacity as renewables will cause instability, causing island-wide blackouts for several hours. Have a look at this site.

Devil I made a small research about solar panels because I am thinking to install them at the house I am building. The way it works is that you are connected to the electricity grid of EAC and you sell the electricity you produce to them for 12c /KWh. They also give a subsidy for 55% percent. Supposedly with the subsidy they give + the money they pay you to sell to them your electricity you will cover all cost of installation within 7 years. And if you don't want to be connected with EAC then you can store the electricity you produce in batteries so you can have power the whole day!

[GerryWolff]

It does not supply electricity to 100,000 homes on a 24/7 basis, as you imply. In fact, the NG plant is operated for <25% of the time to qualify for benefits, so that your implication is, I suggest, deliberately intended to mislead.

As for submarine HVDC connections to this island, the distances are too great from North Africa with today's technology, 100 km being about the practical limit. Furthermore, you would need 4 pairs/poles to ensure reliability for 2 GW at, say 350 kV, 500 MW, in 2015, even if it were possible. However, would you rely on Libya or Egypt to supply Cyprus with electricity? We have seen that Russia can drop oil/gas supplies at the drop of a hat. What would happen if a future President offends Ghadafi or Mubarak or their successors? You cannot simply ignore the political implications. At least with LNG, there are multiple sources available: with a cable with a switch at the other end, you have no choice.

Regarding the capabilities of CSP, the website of the US Department of Energy says ""Solar Two successfully demonstrated efficient collection of solar energy and dispatch of electricity, including the ability to routinely produce electricity during cloudy weather and at night. In one demonstration, it delivered power to the grid 24 hours per day for nearly 7 straight days before cloudy weather interrupted operation." (see http://www.energylan.sandia.gov/sunlab/overview.htm).

It is quite usual for CSP plants to provide gas-firing as a backup source of heat when there is not enough sun. Since the majority of the energy comes from the sun, there is a massive saving in CO2 emissions compared with a power plant that relies entirely on fossil fuels.

Your information about HVDC submarine cables is not up to date. With "HVDC Light" technology from ABB it is feasible to lay submarine cables for 800 to 1000 km. Thus Cyprus could be supplied with CSP electricity from any or all of Lebanon, Jordan, Israel, Egypt, Saudi Arabia or even Libya.

Developing a solar collaboration with countries to the east and south of the Mediterranean would be a good way to build good relations and mutual understandings, a positive alternative to the confrontational policies of Bush and Blair.