Biomass costs

Typical bio-oil production prices are still relatively high Peacocke et al 04 mention values of 13.2-14.6/GJ for FB and rotating cone technology, respectively, based on the assumptions of biomass costs of 50/t dry and feeding rates of 10 dry t/h. 

Biomass cost at plant gale Biomass moisture to gasifier (dry basis) Type of gasifier... 

Figure 7 shows CoE plotted against air oxygen concentration to the gasifier, for a system with an RFSG and a band conveyor dryer. The biomass feed rate is 1.5 dt/h, the pre-dryer biomass moisture content 75% and the biomass cost 630/dt. 

In Figures 8 and 9, the RFSG at various air oxygen concentrations is compared with the UGETC, for a systan with a rotary cascade dryer with integral burner, at a bicenass feed rate of 1.5 dt/h and a biomass cost of 30/dt. 

Similar results are seen at other feed rates, pre-dryer biomass moisture contents and biomass costs. If the RFSG has to operate with oxygen-enriched air however, its superiority in CoE is rapidly eroded. For an oxygen concentration of 0.28 the difference in CoE is negligible for an oxygen concentration above 0.28 the UGETC is usually superior. 

This effect is illustrated in Figures 10 and 11, for systems with an unenriched air RFSG and a UGETC. In each case, the system has a rotary cascade dryer with integral burner, a biomass feed rate of I.S dt/h, a biomass cost of 30/dt and a moisture content to the gasifier of 10%. 

Figure 12 shows the effect of biomass feed rate on CoE for sy ems with an unoiriched air RFSG and a UGETC. The systm has a rotary cascade dryar with integral burner, a biomass moisture content to and frcsn the dry of 7S% and 10%, and a biomass cost of 630/dt. 

The effect of feed rate on fjo is minimal. The effect of feed rate on CoE on the other hand is major, with CoE felling sharply as feed rate increases, particularly at low feed rates. A quadrupling of feed rate results in a halving of CoE. The trends are repeated at other biomass costs and initial moisture contents, and also for systems with the band conveyor dryer. 

Kinds of biomass resources that can be used for energy can be used also for material or food. Therefore, we set bioenergy costs considering opportunity costs of biomass for material or food. If the production cost of a kind of biomass is less than the price of the biomass for material or food, the biomass cost is priced the opportunity cost for material or food. On the other hand, there are disposal costs of some kinds of biomass residues if the biomass has no value except for energy. 

TECHNOLOGY BIOMASS COST /0Dt TECHNICAL RISK POSSIBLE END USE MARKET SHARE... 

Fossil feedstock cost( /GJ) Biomass cost ( /GJ end product)... 

The cumulative effect of incremental process improvement is to cause the raw material costs to eventually become the dominant cost factor. This has already occurred with the oil refining industry and will take place in the biomass processing industries as these are established and grow to maturity. In this regard, biorefineries have a significant potential advantage over petroleum refineries because plant-based raw materials are abundant, widely available and inexpensive. The availability and prices of plant raw materials may thus be more stable and predictable than those of petroleum. As we have seen, plant raw material prices are already comparable on a cost per ton basis with petroleum and coal. Over time, petroleum prices must rise to reflect the fact that it is a nonrenewable resource, while there is the potential to keep biomass costs low indefinitely. 

Solar voltaic cells based on crystalline silicon have operated with a 30% efficiency for experimental cells and 15-20% for commercial units available in 2008, at a cost of around 15 cents/kWh, compared to 4-7 cents/kWh for fossil fuel-fired power plants and 6-9 cents for those fired by biomass. Costs of photovoltaic electricity have shown a continuous downward trend. Part of the high cost in the past has resulted from the fact that the silicon used in the cells must be cut as small wafers from silicon crystals for mounting on the cell surfaces. Significant advances in costs and technology are being made with thin-fllm photovoltaics, which use an amorphous silicon alloy. These cells are only about half as efficient as those made with crystalline silicon, but cost only about 25% as much. A newer approach to the design and construction of amorphous silicon film photovoltaic devices... 

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