Its a good question. My personal view is that costs will drop...

Its a good question. My personal view is that costs will drop once they work out the optimum deployment techniques and operating settings and start (fingers crossed) 'mass' production.

These sort of comparisons are the holy grail of renewable energy. There's lots of information on the web and in various presentations from companies on the ASX. CNM even has some charts in its presentations. These could be a little biased though!

I got the extract below from:

http://www.sddt.com/commentary/article.cfm?Commentary_ID=176&SourceCode=20090820tza

These figures are in US dollars which makes the projected CNM costs ($6 million per MW for commercial demonstration) already competitive with solar. Also, keep in mond, when comparing with non-renewables there are no costs for feedstock (these costs are rising) and no future carbon costs.

The last paragraph is the most relevant one...

"One of the most intriguing questions raised by the new energy paradigm is what physical method should be used to extract the most energy for the least money and return the greatest profit. This seemingly simple concept has taken on an almost mythical quality because of the range of different answers one may reach.

The National Academy of Science, the California Energy Commission, and a host of consultants, developers, speculators and investment houses all want the "simple answer" to the this question in order to guide the wise expenditure of large sums of money. Each has embarked upon a quest for that answer. The simple truth is there is no single answer, but certain technologies lead the pack.
The California Energy Commission’s most recent draft staff report provides costs for twenty-one different energy technologies -- if built by merchant generators.

Remarkably, wind energy has the lowest levelized, tax subsidized cost ($66 to $73 per MWhr), followed by geothermal ($79 to $83 per MWhr), hydro ($67 to $87 per MWhr), coal ($117 per MWhr), conventional combined cycle ($126 per MWhr), solar thermal ($225 per MWhr), and solar photovoltaic ($262 per MWhr). Note that wind energy is one quarter the cost of solar and is well less than coal. These values are based on a government-created predictive mathematical model which includes tax benefits and subsidies.

From a more pragmatic outlook, the actual cost of large scale renewable energy can be viewed from two related perspectives: installed costs, and the value of the electricity produced. Key to typical analyses are "capacity factors" -- the actual percentage of time during which electricity is produced by a particular technology. For example, wind capacity factors range from 35 percent to 45 percent, solar capacity factors are typically 20 percent, demonstrating that the wind blows more than the sun shines during any 24-hour day.

A typical capital cost for a wind facility is roughly $1 million per megawatt on flat land, $3 million on rough, irregular terrain. (Some developers use $2 million per megawatt.) For a desert solar photovoltaic (PV) facility of 10 MW capacity or larger, the cost to build is between $4 million and $5 million per megawatt. A solar-thermal facility’s cost to build is between $4 million and $6 million dollars per megawatt using steel mirrors. By comparison, for smaller, megawatt-sized installations of solar PV, the cost is $5 million to $6 million per megawatt."