Can PV or solar thermal systems be cost effective ways of reducing CO 2 emissions for residential buildings?

This paper compares two solar systems, an actual building integrated, photovoltaic roof (BIPV) and a notional solar thermal system for a residential block in London, UK. The carbon payback for the solar thermal system is 2 years, the BIPV system has a carbon payback of 6 years. Simple economic payback times for both systems are more than 50 years. Calculations considering the current UK energy price increase (10%/yr), reduce the economic payback time for the PV roof to under 30 years.The costs to reduce overall carbon dioxide emissions using a BIPV roof are £196/tonne CO2, solar thermal individual systems at £65/tonne CO2 and community solar thermal at £38/tonne CO2. The current spot market price for CO2 is £15/tonne CO2 (20). Capital costs for PV systems in particular must be significantly reduced for them to be a cost-effective way to reduce CO2. This paper compares two solar systems, an actual building integrated, photovoltaic roof (BIPV) and a notional solar thermal system for a residential block in London, UK. The carbon payback for the solar thermal system is 2 years, the BIPV system has a carbon payback of 6 years. Simple economic payback times for both systems are more than 50 years. Calculations considering the current UK energy price increase (10%/yr), reduce the economic payback time for the PV roof to under 30 years.The costs to reduce overall carbon dioxide emissions using a BIPV roof are £196/tonne CO2, solar thermal individual systems at £65/tonne CO2 and community solar thermal at £38/tonne CO2. The current spot market price for CO2 is £15/tonne CO2 (20). Capital costs for PV systems in particular must be significantly reduced for them to be a cost-effective way to reduce CO2

Is photovoltaic power a cost-effective energy solution for rural peoples in western Sudan?

Sudan like most poor countries suffers from a deficiency in the supply of electrical power, especially for rural areas. Less than 10% of the total population, can benefit from the national grid connection. The paper evaluates the economic, environmental and social issues associated with electrification in western Sudan for rural and nomadic peoples, by assessing three different systems for off-grid electricity supply; stand alone systems powered by diesel generator (gen-set), photovoltaic cells, and a larger distributed generator system (mini-grid). The study indicates that, although photovoltaic might be the best source of electricity from an environmental and social view, unfortunately it currently cannot compete economically. The research identified that Sudanese customs and tax policy adds a significant cost to PV, making diesel generators the best power choice for rural and nomadic regions in Sudan. Other important factors include fuel supply problems and availability of spare parts for generators

Lessons learned from the Pefki solar village in Athens, nearly 20 years on

Solar Village 3 in Pefki, Athens, was part of an ambitious program, with active and passive solar systems providing space and water heating for 1750 inhabitants, designed in the early 80's, and inhabited from the late 80's. This paper focuses on passive solar systems applied to a number of the buildings. A survey highlighted the cases of trombe water benches and conservatories as the most frequently, poorly operated systems. Over time this led to a lack of belief by the occupants in the passive systems. Building simulation indicated a much higher cooling load than originally designed for, combined with recent warmer summers and poor maintenance and operation, have led to the present case that many homes have installed air conditioning. Plans for district heating will improve heating provision for residents and reduce CO2 emissions but a lack of a maintenance strategy for the passive systems will surely lead to their increased neglect

Land Grant Application- Croxford, John (Newburgh)

Land grant application submitted to the Maine Land Office on behalf of John Croxford for service in the Revolutionary War, by their widow Wilmot.https://digitalmaine.com/revolutionary_war_me_land_office/1223/thumbnail.jp

Data visualization within urban models

Models of urban environments have many uses for town planning, pre-visualization of new building work and utility service planning. Many of these models are three-dimensional, and increasingly there is a move towards real-time presentation of such large models. In this paper we present an algorithm for generating consistent 3D models from a combination of data sources, including Ordnance Survey ground plans, aerial photography and laser height data. Although there have been several demonstrations of automatic generation of building models from 2D vector map data, in this paper we present a very robust solution that generates models that are suitable for real-time presentation. We then demonstrate a novel pollution visualization that uses these models