Guest Post by TonyfromOz.
Can wind and solar replace or even compete with coal and nuclear power.?
This article looks at whether wind and solar, as mooted and promoted and subsidised by the Federal government with taxpayers’ money can replace existing coal power or be a viable alternative to nuclear power if coal is phased out.
For replacement of power on this scale, the most important thing to look at is not the Nameplate Capacity of the Plant, the size, but the actual power delivered and that is shown in the fourth column where all bar one are the same, that 69 TWH (TerraWattHours)
This figure of 69 TWH is one third of all the power delivered from coal fired sources in Australia. The total power consumed across the whole of Australia is 300 TWH. The Coal Fired part of that comes in at 230 TWH, and 30% of that is that figure of 69 TWH.
This would be the equivalent of taking out of the current Australian coal fired sector of 4 plants similar in size to Bayswater and Eraring. All power is consumed across the whole of Australia, but the vast bulk of that is on the Eastern side of the Country, so, for this scenario, I would be taking the equivalent of one large scale plant from Queensland, one from Victoria, and 2 from NSW.
I have included Nuclear Power here, full in the knowledge that is for comparison purposes only, as this is something that has very little chance of eventuating in Australia. If it did, first you would need to construct a relatively large full scale Processing plant to take the ore from the ‘raw dirt’ to the fuel rods used in the Plants, and this entails five stages of processing. As well as that, you would also need to construct a reprocessing plant to reprocess the fuel from the spent rods back to the stage where it can be reused at the original processing plant for rods again. Either that reprocessing facility, or a dry storage facility for spent rod storage. All of this requires discussion, legislation, and all that entails, which would be a long process of itself, hence all this prior to actual construction of the Nuclear Power Plant itself.
For new coal fired power, I have used the accepted figure for costing of $525 per KW for construction.
For Nuclear Power I am using current existing technology, and in this case, the most recent Third Generation BWR (Boiling Water Reactor) plants. There will be four of these plants, each plant with two reactors and 2 large generators. The accepted costing figure for construction for these is $2,000 per KW.
For Concentrating Solar 1, I am using a proposed plant Abengoa Solana in Arizona as the guide here. This Plant has a Nameplate Capacity of 250MW, but, as I explained earlier, it can only produce a firm 50MW from total solar, as the compound is kept reserved in a molten State to produce steam to drive the turbine. This effectively means that the total Power delivered is reduced to 50MW and can be available for around 18 hours a day at the maximum. So, that means to actually deliver that 69 TWH in full, you will need 210 of these plants, at the current price of $1.4 Billion.
For Concentrating Solar 2, I am using the same plant, only, instead of diverting the compound, solar is used to produce a firm 150 MW, and it will do this for 12 hours. For the remaining 12 hours, as is the case with Abengoa Solana, they use an on site Natural Gas fired turbine to drive the generator after the solar component becomes less than the molten state required to make steam to drive that turbine. This means the plant can produce a constant 150MW. So, for this purpose, you will need 62 of those equivalent plants to supply the requisite 69 TWH.
Wind is not a relevant comparison because it only has a current Capacity Factor of 20% Worldwide, so it just cannot deliver the power on a 24/7/365 basis. It is claimed that Wind Power could deliver a theoretical Capacity Factor of 38%. This may be the case for individual towers here and there, but when seen over the whole of actual power delivery the World average is that 20% and 25% in the U.S. which has the most recent technology, and for the purpose of this comparison, I have used that higher figure of 25% Capacity Factor, which equates to only 6 hours a day on average.
For Wind power, I have 2 comparisons, the first to actually produce that 69 TWH, and the second to replace just the Nameplate Capacity of those existing coal fired plants, and from that second Wind example you will notice the actual power delivered is only 20 TWH, still only delivered at that 25% Capacity Factor.
For those costings for Wind Power, I will use the costings for a proposed Wind Farm in Queensland, that being the Coopers Gap Wind Farm. This will use nacelles with a 2 MW generator on top of each tower. That farm will have 250 towers producing a Nameplate Capacity of 500 MW. Coopers Gap has a current proposed cost of $1.2 Billion.
(See Figure 1 - below)
(See Figure 1 - below)
Note 1. These plants will consume around 4 million tons of coal each year, hence 16 million tons, and at the average 2.86 multiplier, will emit 46 million tons of CO2, so the saving on emissions from current plants will be around 40% of that original 80 Million tons. Cost A is just the up front construction cost. Cost B includes one refurbishment to take it out from 50 years to 60 years, site clean up, and also 60 years of coal supply of thermal coal at $60 per ton, which is almost double the existing cost of $30 per ton.
Note 2. Refuelling takes place every 18 months, so expired rods can be replaced with new rods. Expired rods are stored on site for the life of the plant, in cooling pools for a further 2 years, and then in dry storage, again, all inside the main reactor concrete bunker which contains the Containment Vessel. If there was a nuclear reprocessing facility, those cooled and dried depleted rods could be sent to that reprocessing facility after those 2 years. Cost A is the up front construction cost, and Cost B included one refurbishment from 50 out to 60 years and site clean up. It also includes the cost of the fuel for that 60 years.
Note 3. As you can see, the enormous up front construction cost is because to supply that 69 TWH you will need 210 of these plants at that $1.4 Billion. Cost B is the equivalent for Coal and Nuclear which have a life span out to 60 years while these Solar Plants have a life of only 20 years, hence you will need three times as many over that 60 years.
Note 4. This is at the 150MW firm basis, hence only 62 of these plants are required, at that $1.4 Billion. The trade off here is the on site Natural Gas fired part of the plant so it can provide that firm 150MW for the full 24 hours. This means an effective emission of just on 350 tons of CO2 per plant per day, hence 128,000 tons of CO2 per annum, and with 62 plants, there will be an emission of 8 million tons of CO2. Cost A is just the construction cost for those 62 plants. Cost B is also an extrapolation out to that 60 years as these plants also have a life span of 20 years. Cost B here will also have added to that figure the cost for the Natural Gas, a significant cost that I HAVE NOT included here, as I don’t have that information, as to the cost of that Natural Gas, but a plant of this type would consume around 5,700 mcf of Natural Gas each day. (mcf is 1000 cubic feet of Natural Gas)
Note 5. This is for the construction of plants that will supply that 69 TWH, although it will only supply that at that 25% Capacity Factor, on average 6 hours a day. Cost B again takes it out to 60 years because these also only have a life span of 20 years.
Note 6. This is for the Nameplate Capacity equivalent, but again, I stress it will not supply that full 69 TWH replacement power, and will only deliver 20 TWH. Cost A is for construction only, and Cost B takes it out to that 60 years equivalent with new coal and Nuclear power.
For the purposes of both Wind plants, I have not included other environmental factors such as bird life and the now recognized human health detriment of Wind Turbine Syndrome. These are anecdotal, and I don’t mean to make light of them, but the main thrust here is for costings and equivalence.
As to references for Costings, I am absolutely certain there will be people who will say that I have grossly underestimated the costs for Coal and Nuclear power, and grossly overestimated the costs for both Wind and Solar, both in an effort to somehow ‘make a case’.
Those figures I have used here for coal and nuclear are costs per KW of Nameplate Capacity. There will be references that some people will find that quote entirely different totals, but be very careful as you read them, keeping in mind I said at the top of the Post that this is a complex thing to understand. Different references use different parameters.
Some costing references will refer to cost per MegaWattHour, (MWH) which is power that is actually provided for consumption. Those costings have included as part of them the ongoing costs of the fuel consumed, both for coal and nuclear plants, and these costs are referred to as levelised costs. To cover that contingency, I have included Cost A as construction only and Cost B as whole of life cost, which is the same as levelised cost per MWH.
At some sites, you will also see vastly more expensive costs for coal fired power, because they have included the horrendously expensive ‘extra’ of CCS, Carbon Capture and Storage, a fantasy dream that will never be realized on the scale required, so those costings you see for that can be totally ignored.
As for inflating the costs of Wind and Solar, I have used current data for plants that have already been proposed or are already in construction. A prime example of cost blowouts here is for Cape Wind in Massachussets. The original cost was for $800 million, which has now ballooned out to $2.5 billion.
For both Wind and Solar,I have also included Cost A and Cost B, as these plants only have a life span of 20 years as opposed to coal and nuclear which can be extended out to 60 years, hence Cost B has multiplying factor of 3.
As you can plainly see both new coal and nuclear are significantly less expensive than any of the renewable replacements, even with the inclusion of the price of the fuel for both.
Again, be fully cognizant of the fact that Nuclear power is not an option for Australia, possibly for decades.
Remember, this is a hypothetical exercise, and while I have attempted to cover all the bases, this is a much simplified exercise. The costings are as accurate as I currently have access to.