With GTM’s sixth annual Solar Summit less than three weeks away, we're taking a closer look at the topics and themes that will come under the microscope. As always, module costs continue to be an area of considerable interest. Module costs for best-in-class Chinese producers such as Jinko Solar and ReneSola are set to drop below the 50 cent per watt mark in 2013 -- something which few (if any) industry roadmaps anticipated. There is currently little clarity around variables like what the cost curve looks like from here on out, the ultimate cost floor for manufacturing modules, and how we'll get there.

These are precisely the themes that will be tackled on a panel titled "Where Will Module Costs Bottom Out?" at the Solar Summit. Joining the discussion will be some battle-scarred industry veterans that live and breathe solar manufacturing: Charlie Gay (President,  Applied Materials Solar), Jeff Zhou (President, Hanergy Holding America), Chris Eberspacher (Chief Technology Officer, Hanwha Solar) and Bryan Ashley (Chief Marketing Officer, Suniva). Below are some of the topics we'll be discussing.

Roadmaps and Benchmarks: Back in 2009-2010, industry roadmaps were targeting $1/W module costs as a medium-term goal. Now, producers such as ReneSola and First Solar are approaching costs of $0.50/W, with the rest of the industry not far behind. What does this mean for industry cost roadmaps from here on out? What is a realistic goal for the module supply chain to set for itself over the next three to five years? Or should the emphasis shift toward higher efficiency in order to lower BOS, even if it means increasing module costs?

Efficiency Tradeoffs: It is well understood that efficiency is a key lever in the cost reduction equation. But beyond a certain point, efficiency increases will not come for free; instead, they will come at the expense of additional capital investment and/or process complexity. How far can we keep pushing the efficiency needle until the costs outweigh the benefits in terms of module manufacturing costs?

Consumables Costs: A significant proportion of the cost declines we have seen in the last year or so have come from pricing reductions in consumables like crucibles, wire, slurry, frames and encapsulants. Given that a lot of the pricing reductions have come from margin evaporation as opposed to cost reduction, to what extent are these sustainable, especially given that many of these materials are approaching commoditization?

Technology Investment Cycles: There are a number of new, market-ready technology platforms and concepts available that seem to promise meaningful advances in improving the cost/efficiency equation for PV (examples: FBR silicon, continuous CZ ingot growth, diamond wire sawing, reformulated metallization pastes, frameless modules). But capital investment in anything but incremental upgrades seems to have screeched to a halt since mid-2011. Is the current manufacturing downturn holding back technological progress, and could it slow down cost/efficiency improvements in the long run, if and when consumables pricing flattens out?

Evolution Versus Revolution: Looking at the evolution of cell technology concepts over the last twenty-odd years, we have seen incremental changes in device structure and process flow -- in other words, evolution not revolution. Looking ten years into the future, however, is there a possibility of a fundamentally different technology concept being the industry standard because of the cost/efficiency of crystalline Si hitting a wall?

N-Type Technology: There has been a lot of interest in N-type technology in the last eighteen months, but it seems there are a lot of technology and supply chain barriers standing in the way of cost-competitiveness in the near term. What are the potential implications of this?

Hanergy and Thin Film: Hanergy's continued commitment to thin film stands out amidst the challenges faced by many thin film firms in recent times. With $/W feedstock costs for CIGS and c-Si now roughly the same, what is thin film's competitive advantage? What drives investment decisions in the thin film space, both with respect to amorphous silicon technology and the acquisitions of MiaSolé and Solibro? Is Hanergy an isolated example of a successful thin film firm due to its large balance sheet and cutting-edge manufacturing assets, or is it the beginning of a more widespread industry shift away from c-Si over the long term?

Have a question to ask? Let us know in the comments section below, and we'll pose it to the panelists at the show.

Greentech Media's sixth annual Solar Summit will be held from April 22-24 in Phoenix. For more information, click here.