Archives 2009

Rising inventory levels of photovoltaic (PV) panels and new production capacity coming online is driving solar PV prices lower and thereby, bringing solar energy closer to grid price parity. With the release of the latest earnings of solar energy companies, Wall Street’s keen attention to revenue guidance, inventory levels and pricing are paramount in diagnosing the health of the solar energy industry. Expectations call consolidation of the solar industry with some key players gaining market share and for others it becomes more challenging. However, despite the turbulence in the industry, consumers will benefit in the near-term as solar PV prices fall and government incentive fuel growth in solar PV deployment.

To get a better perspective on the solar PV industry, let’s examine inventory levels for some of the leading solar PV suppliers. The following chart, Figure 1, compares inventory levels in relationship to sales volume. While inventory levels have increased, the level of inventories to sales is not egregious

Figure 1 Sales and Inventory levels

While it is important to control inventory levels in relationship to sales, revenue growth is predicated upon price, performance, and return on investment for prospective customers. Thin-film PV has emerged as the low-cost solar solution even with its lower efficiency levels in comparison to mono-and poly-crystalline PV panels. Thin-film still offers a lower cost/watt than crystalline PV, see Solar Shootout in the San Joaquin Valley , but prices for crystalline PV are falling as a result of rising production capacity and inventory levels.

Figure 2 Market Value

In Figure 2 Green Econometrics is comparing the market value of some of the leading PV suppliers as measured by their respective stock prices. In the valuation of solar PV suppliers, the stock market appears to be betting heavily on thin-film PV, as First Solar (FSLR), the leading thin-film PV supplier, enjoys a market value that accounts for over half the value of the entire solar industry. FSLR is positioned as the low-cost supplier in the solar industry with its announcement of $1 per Watt reducing its production cost for solar modules to 98 cents per watt, thereby braking the $1 per watt price barrier. However, new panel suppliers, mainly from China are pushing prices lower for poly-and mono-crystalline panels suppliers. ReneSolar (SOL) is seeing average selling prices for wafers at $0.93 per watt and bring PV panels prices to under $2.00 per watt.

There appears to be a lot riding on the success of thin-film PV and as prices fall for crystalline PV, the closer we get to grid parity. In the following chart, Figure 3, price for crystalline PV have declined quite dramatically in the last 30 years. According to the Energy Information Administration, in 1956 solar PV panels were $300 per watt, and in 1980, the average cost per solar modules was $27/watt and has fallen precipitously to approximately $2/watt in October 2009. As the installed cost of solar PV falls closer to $4/watt, pricing per kilowatt-hour (KWH) (depending on your climate and geography), equates to approximately $0.16/KWH that would be inline with utility rates after rates caps are removed.

Figure 3 Solar PV Prices

The bottom line is that despite the lower PV panel costs; we are still not at parity with hydrocarbon fuels such as coal and oil. Carbon based taxes or renewable energy incentives as well as more investment into alternative energy should improve the economics of solar and wind and bring us to grid parity.

A combined heat and power system (CHP) is the cogeneration or simultaneous generation of multiple forms of energy in an integrated system. CHP systems consume less fuel than separate heat and power generating systems. According to the Environmental Protection Agency in their Combined Heat and Power Partnership report, (EPA), CHP systems typically consume only three-quarters the amount of energy separate heat and power systems require. By combining both heat and power into the same energy systems, efficiency gains for the total system. Heuristically, high temperature and high pressure fuel ratios results in higher efficiency systems. In addition, the thermal energy produced from the CHP system could be used to drive motor applications or to produce heat, steam, and hot water.

As an initial step to reducing greenhouse gas (GHG) emissions, natural gas turbines could improve overhaul efficiency of 65-80%. In addition, the CHP offers lower greenhouse gas (GHG) emissions in comparison to conventional standalone systems. Gas turbines CHP systems operate under a homodynamic principle called the Brayton cycle. The design characteristics of a CHP gas turbine provide: 1) high electric and total system efficiency; 2) high temperature/quality thermal output for heating or for heat recovery steam power electric generation; 3) offer options for flexible fuels such as propane, natural gas, and landfill gas; 4) high reliability with 3-to-5 years before overhaul running 24/7; and 5) significantly lower GHG emissions.

Figure 1 Gas Turbine CHP System

Figure 1 demonstrates the mechanics and variables of a CHP system. In summary, the CHP technology enables the supply of efficient heat and power while minimizing GHG emissions. Total CHP efficiency is defined as the sum of net power produced plus the thermal output used for heating divided by total fuel input.

The use of methane (natural gas) as the main fuel for the CHP system offers advantages because methane offers the highest hydrogen-to-carbon ratio among fossil fuels, thereby, combusting with the lowest GHG emissions. According to EPA data, the emissions NOx particulates from gas turbines ranges between 0.17-to-0.25 lbs/MWH with no post-combustion emissions control versus 1.0-to-4.2 lbs/MWH for coal fed boilers. The carbon content of natural gas is 34 lbs carbon/MMBtu in comparison to coal at 66 lbs of carbon/MMBtu.

There are two valuable metrics used to measure efficiency for CHP systems. One is the total system efficiency which measures the overall efficiency of the CHP system including heat and electric and the other is the effective electric efficiency which is useful in comparing the CHP electric production versus grid supplied power. These two metrics, the total system and effective electric efficiencies are important for evaluating CHP system. The following provides a guideline foe measuring these two efficiency metrics and can be found at EPA – Efficiency Metrics for CHP Systems

Figure 2 CHP Efficiency

The economics of the CHP system depends on effective use of thermal energy n the exhaust gases. Exhaust gases are primarily applied for heating the facility and could also be applied to heat recovery steam generators (HRSG) to produce additional electric power. The total efficiency of the CHP system is directly proportional to the amount of energy recovered from the thermal exhaust. Another important concept related to CHP efficiency is the power-to-heat ratio. The power-to-heat ratio indicates the proportion of power (electrical or mechanical energy) to heat energy (steam or hot water) produced in the CHP system. The following provides an overview of the economics of a CHP system.

Figure 3 CHP Economics

Figure 3 illustrates the economics of a CHP system in comparison to competing energy sources. While the CHP does not have the low cost of coal in producing electric, the economic value of reducing GHG emissions is quite significant and beyond the scope of this article. However, natural gas prices remain below that of oil and better ways of capturing heat exhaust will further improve CHP efficiency. The bottom line is that natural gas produces less GHG emissions than coal or oil therefore; businesses should consider the benefits of CHP as a source of heat and power.

The development of an energy efficiency strategy incorporates analysis of energy expenditures and energy consumption. The energy strategy must incorporate dynamics between costs, budgets and the consumption of energy including the monitoring of kilowatt-hours (KWH) of electricity and liquid hydrocarbon fuels consumed. By analyzing both the financial and the energy consumption components we are better positioned to frame the scope of the energy efficiency projects.

We start with a comprehensive energy audit analyzing energy consumption and expenditures. After determining which activities offer the fastest, cheapest, and greatest economic impact we are then able to define the scope of energy efficiency projects. The next step in the energy strategy process is to assess, rank and specify energy saving opportunities. At this phase, we have a broad understanding of the scope of energy efficiency projects within the appropriate budgetary considerations.

Conduct Energy Audit and Analyze Energy Spending

Upon analysis of the energy expenditures and the appropriate budgetary considerations, we commence with an energy audit to examine the dimensions of energy consumption. The energy audit establishes an energy efficiency baseline for buildings and vehicles. In the energy audit, energy consumption is measured by source and activity using monitors attached to branch circuits, gas pipes, and fuel lines. In this manner, energy consumption is evaluated from a financial and physical perspective and baseline usage patterns are established for electricity and other fuels.

During the energy audit, an analysis of energy intensity is measured. For buildings, energy consumption is measured in kilowatt-hours per square-foot to identify which activities consume the most energy. The energy intensity measurements are then ranked by consumption activity and compared to actual energy expenditures.

The purpose of the energy audit is to establish a baseline of energy consumption and the energy intensity associated with each building, department, vehicles, and/or activity usage category. By constructing an effective energy efficiency strategy that identifies and measures energy demand by activity, a better understanding of economic- and financial-impact is established. The critical component to the energy audit is measurement and verification were wireless Internet-based energy monitoring provide data before and after energy efficiency projects commence. The energy audit and energy monitoring systems together with financial analysis of energy consumption serve as the framework to rank and assess energy efficiency projects.

Heuristically, energy consumption in buildings is tied to lighting; and heating, cooling, and ventilation systems see Energy Intensity . The following chart, Figure 1 serves to illustrate which activities contribute most to energy consumption in buildings.

Figure 1 Kilowatt-hours (KWH) per Square Foot

According to information provided by the DOE, lighting, cooling and ventilation alone account for nearly two-thirds of all energy consumption in a building. For perspective, electric energy demand is increasing at an annualized rate of 1.6%. According to the Energy Information Administration (EIA), demand for electricity grew 21% between 1995 and 2006.

The energy consumption audit provides a means to assess which activities should be further analyzed for energy efficiency projects. The baseline energy usage measured in KWH per square foot serves as the framework to evaluate that locations and activities could benefit from lighting retrofits, equipment upgrades, structural improvements, and energy monitoring systems.

As a consequence of increasing energy consumption in buildings, electric generation relies extensively on hydrocarbon fuels that carry adverse environmental effects. Figure 2 illustrates the proportion of coal and other hydrocarbon fuels that are used to generate electricity in comparison to renewable energy sources. Coal still accounts for nearly half of all electric generation while contributing the most in terms of harmful emissions such as carbon dioxide, nitrous oxide, and sulfur dioxide.

FIGURE 2: Electric Generation Method

As part of the energy audit process for buildings, an energy consumption analysis of lighting and HVAC systems is evaluated along with the building’s insulation R-Value (resistance to heat flow where the higher the R-value, the greater the insulating effectiveness). In addition to lighting and HVAC systems, specialized equipment may also account for large energy demand. During our energy audit, we plan to identify and measure energy usage of special equipment in order to construct energy efficiency initiatives with clearly defined and measurable energy reduction targets.

Energy efficiency for transportation vehicles is one of the most significant factors to manage. The fact that there are no real substitutes for oil in the transportation industry illustrates two important points: 1) structural changes to driving patterns are required to see appreciable changes to oil consumption and 2) government authorities are vulnerable, with no readily available substitutes for oil, supply disruption could negatively impact transportation systems. Therefore, we emphasize fuel management systems for fleets and vehicles that monitor fuel consumption and efficiencies. DOE studies have indicated that changing driving habits could improve fuel efficiency by up to 30%.

Vehicle mounted devices that integrated fuel consumption feedback as the vehicle is driven promotes higher fuel efficiency. These off the shelf products are cost-effective, offering payback in months that dramatically improves fuel efficiencies. Aside from routine tune-ups, limiting weight, and checking tire pressure, augmenting driving patterns through gauges that provide feedback on fuel efficiency make the difference in saving energy.

In most situations, fuel management systems can be installed without significant mechanical aptitude. The ScanGaugeII from Linear-Logic is useable on most vehicles manufactured after 1996 including Gas, Diesel, Propane and Hybrid Vehicles and are designed to be installed by the consumer with plug-and-play instructions.

Identify and Measure Energy Demand by Activity

From the Energy Audit, the energy intensity of targeted buildings and fuel efficiencies of official vehicles are established. In buildings, it’s the lighting and heating, ventilation, and cooling that comprise the bulk of energy consumption.

Heating, ventilation, and cooling represent a significant portion of energy consumption in buildings and are a priority target for energy analysis. The Seasonal Energy Efficiency Ratio (SEER) is employed as an assessment of the equipment and analyzed in conjunction with building insulation. The efficiency of air conditioners is often rated in SEER ratio, which is defined by the Air Conditioning, Heating, and Refrigeration Institute and provides a standard unit measure of performance. The higher the SEER rating of a cooling system the more energy efficient the system is. The SEER rating is the amount of BTU (British Thermal Units) of cooling output divided by the total electric energy input in watt-hours.

For heating systems in a building, Annual Fuel Utilization Efficiency (AFUE) is used to measure and compare the performance of different systems. DOE studies have indicated that even with known AFUE efficiency ratings, heat losses defined as idle losses contribute to degradation in heating system efficiency,

To analyze energy consumption of heating and air conditioning systems (HVAC), we evaluate the building’s R-Value in comparison to the energy efficiency of the current heating and air conditioning systems. The energy demand evaluation includes a cost-benefit analysis comparing options in either HVAC system upgrade and/or improvements to the building’s insulation R-Value. By comparing the buildings R-Value in conjunction with HVAC efficiency performance, projects offering the greatest cost effectiveness are identified. The building’s R-Values can be measured using FLIR Systems infrared camera and software system. In this manner, the replacement cost of an HVAC system and costs to improve the building’s R-Value are analyzed to measure economic benefits. This information will allow the building owner to make an informed decision on whether any energy efficiency investment into HVAC upgrade or improvement to R-Value demonstrate economic benefit, i.e. positive financial return.

Consideration for heating and cooling systems upgrades are assessed by equipment SEER and AFUE ratings, installation costs, and efficiency payback. After equipment assessment is complete, proposals will be provided along with estimates for upgrade costs and payback analysis.

Benchmark and Analyze Energy Intensity

After conducting the energy audit, and compiling data on energy usage by activity category, we benchmark and analyze energy projects offering the greatest opportunities. As illustrated in Figure 3, energy efficiency for lighting systems can be substantially improved by retrofitting legacy light fixtures with higher efficiency fixtures and bulbs.

The energy audit and analysis provide the framework to evaluate energy efficiency projects. By analyzing energy consumption and the economic benefits associated with the energy savings projects, the most efficient and economically beneficial initiatives are identified and ranked.

FIGURE 3: Energy Savings in KWH per Square Foot Figure 1 Kilowatt-hours (KWH) per Square Foot

Establish Measurable Goals and Objectives

To establish relevant goals and objectives we are evaluating projects that are adhering to the SMART goal approach: specific, measurable, attainable, realistic and timely. Energy efficiency gains are most pronounced with lighting retrofits and energy monitoring in buildings in buildings and energy monitoring in vehicles.

After conducting an energy audit, analyzing energy consumption activities and the economics of energy efficiency projects, realistic and achievable energy savings goals are defined. Key performance metrics for energy savings are defined for buildings and vehicles. Key performance indicators are established for each project. For example, KWHs saved are defined for lighting retrofit projects, efficiency improvements for HVAC system upgrades, R-Value improvements for building insulation, and MPG gains for vehicles.

For each energy savings project, timelines are established with clearly defined milestones. Energy projects are presented with costs; expected energy savings measured in energy and dollar units, cost benefit analysis, and timelines.

Architect the Deployment of Energy Monitoring Systems

One of the first energy initiatives to consider in any energy savings project is the installation of an energy monitoring system for vehicles and buildings. Energy monitoring systems demonstrate the fastest and most economical pathways to achieving energy savings.

Energy monitoring systems for motor vehicles also demonstrate positive economic returns and real energy savings. The $180 energy-monitoring device with 10% fuel efficiency gain achieves breakeven at 14,500 miles with gasoline costing $2.50 a gallon.

Evaluate Feasibility of Renewable Energy Projects

Renewable energy projects such as solar and wind energy systems are often costly with long payback periods. Without tax incentives and grants, renewable energy projects are unable to demonstrate positive financial returns. However, utility rates for electric are expected to increase, improving the case for renewable energy projects. To improve the viability of alternative energy projects, energy efficiency projects such as lighting retrofit serve to lower energy consumption and therefore enhance the feasibility of solar and wind energy projects.

The fall in oil consumption was most dramatic following the escalating price of crude oil to $145.16 per barrel on July 14, 2008 then at any other point over the last several years. Price elasticity, a key concept in Economics 101, which measures the impact of price change to changes in unit volume sold, is helpful in determining which products have readily available substitutes or which, like oil are inelastic with no real substitutes.

As illustrated by Benjamin Graham and David Dodd in their book Security Analysis, 1940 edition, during the 1930’s the economy had a dramatic impact on spending and consumption particularly on discretionary items such as travel. In one illustration, the change in demand was most pronounced in railroad revenues where tickets purchased for railroad travel, declined 51% from 1929 to 1993 as measured by gross receipts for the railroad industry. Over this same period, spending on the consumer staples (inelastic demand), such as electricity encountered a decline of only 9%.

While almost everyone would agree that the current economic climate is one of the most challenging since the 1930’s, a quick review of oil consumption over the last several years illustrates that demand has not significantly contracted, suggesting driving habits only changed when prices escalated to over $100 per barrel. Oil consumption dropped only 4.9% from January 2008 through January 2009.

Figure 1 Oil Consumption

As seen from Figure 1, the sharp drop in oil consumption in September 2008 of 8.3% appears as an aberration when measured over the whole year. The fact there are no real substitutes for oil in the transportation industry illustrates two important points: 1) structural changes to driving patterns are required to see appreciable changes to oil consumption and 2) how vulnerable we are as a nation with no readily available substitutes for oil in the transportation systems.

Figure 2 Oil Demand in China and India

With China and India undergoing significant structural changes as they rapidly migrate towards motor vehicles for transportation suggests the demand for oil should continue to grow relatively unabated. Until the price of oil climbs back over $100 per barrel, we will not see the structural changes necessary to develop alternatives to oil in the transportation market.

The bottom line: energy and in particular, oil has not experienced a dramatic drop in demand during 2008 suggesting driving patterns were influenced more by the price of oil then the struggling economy. We must begin to shift emphasis to alternative energies such as solar as well as hybrids and electric vehicles.

Last month First Solar (FSLR) achieved a milestone in the solar industry with its announcement of $1 per Watt reducing its production cost for solar modules to 98 cents per watt, thereby braking the $1 per watt price barrier.. While the achievement is great news for the solar industry some studies suggest more work is needed. An article in Popular Mechanics $1 per Watt talks of university studies questioning the scalability of solar given the immense global needs for energy. Last year our post included an article Solar Energy Limits – Possible Constraints in Tellurium Production? discussing possible limits on tellurium production on thin film solar photovoltaic (PV) suppliers.

In addition, Barron’s published an article (March 30, 2009)_ Nightfall Comes to Solar Land providing unique insight into the economics of solar PV suppliers. High oil prices and soaring stock prices on solar PV companies fueled silicon suppliers to ramp production capacity that has now transitioned, according to the Barron’s article, into an over supply of polysilicon used in the production of PV panels and subsequently, eroding the cost advantage established by thin film PV companies such as First Solar and Energy Conversion Devices (ENER) over polysilicon PV firms such as SunPower (SPWRA).

However, the PV panels typically represent approximately half the cost of a solar energy system. The following figure, Solar Installation Costs compares the total cost of installing a solar energy system which includes labor and supporting matertials.

Figure 1 Solar Installation Costs

As illustrated in Figure 1, the panels represent a significant cost of installation, but the labor and support brackets for the PV panels are significant as well. While thin film PV enjoys significantly lower panel costs and is easier to install, the supporting brackets are sometimes more expensive. As prices for silicon fall, the cost disparity between thin film and silicon PV will narrow.

Figure 2 Solar Energy Economics

In Figure 2 Green Econometrics is comparing PV efficiency as measured by watts per square meter versus cost per watt. The selected companies represent a small portion of the global PV suppliers, but do illustrate the position of the leading US suppliers. The ideal model is to lower cost per watt while improving PV efficiency. But be cognizant that PV module cost per watt may not be indicative of the total system costs.

A comparison of wind and solar energy costs is demonstrated by Detronics and offers a useful framework to compare wind and solar costs by kilowatt-hour (KWH). As a caveat, wind and solar resources will vary dramatically by location. In the Detronics example, the costs per KWH represent the production over one year and both wind and solar have 20-year life spans. Over twenty years the 1,000-watt wind systems cost per KWH of $7.35 would average approximately $0.36 per KWH and the 750-watt solar systems cost of $10.68 would amount about $0.53 per KWH over the investment period.

Figure 3 Alternative Energy Pricing

The Alternative Energy Pricing chart was base on research from Solarbuzz which is one of the leading research firms in solar energy. The cost per KWH that Solarbuzz provides is a global average. Even with cost per watt falling below $1.00, the system costs after installation are closer to $5.00 according to Abound Solar (formerly known as AVA Solar) and is still higher than parity with grid with a cost of $0.21 per KWH.

The bottom line is that despite the lower PV panel costs; we are still not at parity with hydrocarbon fuels such as coal and oil. Carbon based taxing or alternative energy stimulus and more investment into alternative energy is required to improve the economics of solar and wind.

America’s appetite for oil declined sharply as the economy weakened over 2008. According to the latest reported information from the Energy Information Administration (EIA), Monthly Oil Consumption oil consumption declined 13% y/y from September 2007 through September 2008.

Historically, the US has seen this type of demand erosion before. From 1979 to 1983, oil demand in the US declined 28% with annualized rate of a 10% decline per year. Over this same period, oil prices actual rose despite the fall in demand. Oil prices by barrel (42 US gallons) rose from $3.60 in 1972 to $25.10 in 1979. In 1983, oil prices increased to $29.08 a barrel, representing an increase of nearly 16% from 1979.

Economics would normally dictate that as demand declines so should prices. However, the geopolitical events and oil supply disruption maintained higher oil prices despite the subsequent decline in oil demand. It was not until structural changes in energy conservation and driving patterns were felt before leading to a fall in oil prices during the 1980’s.

Figure 1 Monthly Oil Consumption

As illustrated in Figure 1, the precipitous fall in oil demand over the last half of 2008 is quite dramatic in comparison to historical price data. The large fluctuations in monthly oil consumption during the 70’s and 80’s, were primarily due to supply disruptions. The higher oil prices resulting from supply disruptions over this period led to structural changes in the energy market that later resulted in falling oil prices.

Figure 2 Oil Prices

While falling demand and rising oil prices during the 70’s and 80’s is an anomaly, we see from Figure 2, that currently there is significant correlation between falling oil demand and a subsequent decline in the price of oil. Excluding the peak oil price in July 2008, oil declined 33% from the average price per barrel of $64 in 2007.

Perhaps the precipitous fall in oil prices can explain why demand for oil on a global basis has not declined as dramatically as in the US. As we can see from Figure 3, the drop in US oil consumption is matched with a slight increase in demand in Europe and only a moderate decline in Japan.

Figure 3 Global Oil Demand

The bottom line is the financial shock that hit global markets is dramatically impacting consumption. As a recovery inevitably ensues, demand for oil will increase and so will oil prices. Let’s not be complacent with hydrocarbon fuels. Falling energy prices act as a disincentive for investment into alternative energies.

As President Obama takes office, energy efficiency takes center stage. One of he fastest roads to energy efficiency is to reduce consumption and the simplest approach to energy conservation is to change a light bulb.

Compact Fluorescent Light bulbs (CFL) recommended by the U.S. Department of Energy (DOE) offer substantial savings to homeowners. In the commercial market, lighting fixtures consume the greatest amount of electric energy; three times the energy consumption of air conditioning. According to research report from the Energy Information Administration (EIA), Commercial Buildings Energy Consumption Survey lighting consumes the largest amount of electricity in commercial buildings as measured by Kilowatt-hours (KWH) per Square Foot

To calculate KWH, multiply the wattage of your lighting fixture x the yearly hours of operation for your facility divided by 1,000. KWH per square foot provides a useful means of measuring the energy intensity of a building. Just divide KWH by the total square footage of the building.

In an energy audit one can determine the energy intensity of your building as measured by KWH/Sq Ft. Figure 1 illustrates the energy intensity by end use according to the EIA’s report in 2008 Electricity Consumption (kWh) Intensities by End Use.

Figure 1 Lighting Consumes Most Energy

Furthermore, as part of the same research from the EIA, most commercial buildings are not using energy efficient lighting. The study finds that most commercial buildings, even those built after 1980, still rely on legacy incandescent and standard fluorescent light fixtures.

Figure 2 Most Commercial Buildings Lack Energy Efficient Lighting

After your energy audit is complete and one knows their energy intensity the next step is to understand the efficiency of lighting systems. Lighting efficiency is measured in Lumens per Watt and is calculated by dividing the lumen output of the light by the Watts consumed. A lumen is one foot-candle foot-candle falling on one square foot of area.

While lumen output is important in measuring brightness, color temperature, measured in degrees Kelvin, indicates the hue color temperature of the light and is also important in evaluating lighting systems because lighting systems operating near 5500 degrees Kelvin simulate sunlight at noon. Energy efficient lighting fixtures provide twice the lumens per watt of electricity than legacy metal halide fixtures while offering higher color temperature enabling near daylight rendering.

Figure 3 Energy Efficient Lighting

The bottom line is small steps sometimes produce big results. Retrofitting your building with energy efficient lighting systems saves energy, reduces operating expenses, and improves employee productivity and safety, while saving the environment. A 1.3 KWH reduction in power consumption reduces carbon dioxide (CO2) emissions by 1 pound. Coal generates about half the electric power in the U.S. and produces roughly ¾ of a pound of CO2 for every KWH of electric. In addition, the feasibility of alternative energy such as solar and wind are more viable by reducing energy consumption in buildings.