Energy Guides: Buildings, Fuels, Power and the Environment - Yenra

Practical guides to energy projects, batteries, electricity offers, fuels, generation and storage, with historical reporting by subject.

Evaluate building energy projects, choose compatible equipment and electricity offers, and understand fuels, storage and the power grid. Start with the practical guides below, then explore background reporting by subject.

Plan building energy and electricity purchases

Cost of Solar Energy: Compare Quotes and Estimate Savings

Compare rooftop solar proposals using installed cost, production, utility tariffs, financing and a worked savings example.

Energy Conservation Tips: Build a Practical Home Plan

Prioritize home energy actions, account for equipment and comfort needs, and track changes using bills and simple measurements.

Smart Electric Meters: Understand Usage and Rate Options

Use interval meter data to distinguish power from energy, check a bill and compare time-of-use rates with a worked example.

Cool Roofs: Evaluate Heat Reduction and Roof Suitability

Compare cool-roof proposals using climate, roof condition, aged material ratings and the difference between surface cooling and building savings.

Biomass Boilers: Evaluate Fuel, Heat Demand and Operating Requirements

Screen biomass heating proposals using the building heat profile, fuel specification, delivered heat cost, storage, maintenance and emissions requirements.

Energy Efficiency: Evaluate Upgrades and Verify Savings

Compare building efficiency proposals using a clear baseline, consistent service conditions, complete costs and a plan to verify savings.

Green Power: Compare Renewable Electricity Offers and Claims

Compare U.S. renewable-electricity offers using cost, contract terms, renewable energy certificates and evidence supporting the advertised claim.

Prepare for interrupted power

Battery Backup: Choose and Size a UPS

Choose a UPS for computers and networking equipment using measured loads, watt and VA limits, runtime curves and shutdown requirements.

Blackout Power Outage Safety: A Household Plan

Prepare for a power outage, protect food and essential equipment, and decide when to move to a safer place.

Backup Generator: Plan Loads, Fuel and Installation

Build an essential-load plan, compare portable and standby backup options, and prepare a complete brief for a qualified installer.

Fuel Cell Backup: Evaluate Critical Loads, Runtime and Readiness

Prepare a critical-load backup brief covering battery bridging, net electrical output, fuel endurance and documented readiness.

Choose equipment and manage fuel costs

Car Batteries: Choose the Correct Replacement

Identify the correct automotive starting or auxiliary battery using vehicle fitment, chemistry, ratings and service requirements.

Universal Plug Adapter: Check Voltage and Compatibility

Read device input labels, check destination supplies and choose travel power accessories with the correct grounding and ratings.

Sealed Lead-Acid Batteries: Match the Battery, Load and Charger

Prepare a replacement specification for a sealed lead-acid battery using approved models, discharge data, terminals, dimensions and charging requirements.

Outdoor Bug Lights: Choose Lighting That Attracts Fewer Insects

Choose porch and patio lighting using spectrum, brightness, shielding, controls and fixture ratings, with realistic expectations about insect attraction.

Gas Prices: Understand Pump Prices and Estimate Fuel Costs

Compare like-for-like gasoline prices, interpret regional averages and calculate trip costs and the fuel-only value of a detour.

NiMH Batteries: Understand Capacity, Charging and Compatibility

Read NiMH battery specifications, choose supported cells and chargers, and distinguish ordinary rechargeable cells from managed hybrid-vehicle packs.

Digital Camera Batteries: Choose Compatible Power and Plan Runtime

Identify approved camera batteries and charging options, interpret test ratings, and plan spare power for still photography or video.

Fuel Cell Vehicles: Evaluate Refueling, Range and Ownership Fit

Check a hydrogen vehicle against your routes, operating stations, fuel costs and service support before choosing an exact model.

Biodiesel Vehicles: Check Blend Compatibility and Fuel Requirements

Identify the approved biodiesel blend, fuel specification and operating requirements for a particular diesel vehicle or fleet.

Electrical Safety Switches: Understand Disconnects, Ratings and Protection

Understand enclosed disconnect terminology and gather the documentation a qualified electrician needs to assess switching equipment.

Diesel Engines: Understand Fuel, Emissions Controls and Operating Needs

Separate diesel fuel economy, particulate and NOx controls, and carbon emissions when evaluating a vehicle or machine for its duty.

DC-DC Power Converters: Compare Ratings, Losses and Thermal Limits

Build a DC-DC converter requirements record using input range, output behavior, isolation, losses and the actual thermal environment.

Diesel Generators: Evaluate Duty Ratings, Fuel and Readiness

Prepare a facility generator brief that connects operating duty, load behavior, site conditions, fuel endurance and readiness records.

Hybrid Electric Buses: Evaluate Routes, Fuel Use and Fleet Fit

Compare hybrid buses using matched routes, fuel and service data, exact vehicle configurations and fleet support requirements.

SEPIC Converters: Understand Operation and Design Tradeoffs

Understand the SEPIC switching cycle, ideal duty-ratio relationship and component stresses before evaluating a low-voltage DC design.

Direct Methanol Fuel Cells: Evaluate Portable Power and Runtime

Evaluate direct methanol power systems using net output, battery buffering, approved fuel, operating conditions and a consistent runtime calculation.

Hybrid Powertrain Simulation: Plan a Hardware-in-the-Loop Test

Define a powertrain controller test using a clear model boundary, timing budget, signal map, fault scenarios and acceptance criteria.

Hydrogen Combustion Vehicles: Evaluate Efficiency, Emissions and Storage

Compare hydrogen-engine claims using the propulsion pathway, duty cycle, fuel consumption, emissions evidence and complete onboard storage system.

Zinc-Air Energy Systems: Understand Discharge, Refueling and Regeneration

Distinguish zinc-air system types and evaluate energy, peak power, recharge or refueling, and the material-regeneration boundary.

Power Integrity Simulation: Interpret Voltage Drop, Impedance and Transients

Choose a chip power-delivery model boundary and interpret DC voltage drop, impedance peaks and load-step behavior with a clear voltage budget.

Integrated Power Switches: Read Ratings, Losses and Protection Features

Read an integrated offline power-switch datasheet using operating conditions, power capability, losses, thermal limits and fault-response requirements.

Understand generation, storage and grids

Nuclear Power Advantages and Tradeoffs: Evaluate the Claims

Compare nuclear electricity using operating evidence, lifecycle boundaries, construction risk, grid value and waste-management responsibilities.

Power Outage Causes: Local Faults and Grid Failures

Understand local outages, protective switching and cascading grid failures, with the official findings from the August 2003 blackout.

Wind Power: Understand Output, Siting and Project Tradeoffs

Interpret wind projects using rated capacity, annual generation, site evidence, grid connection and local operating impacts.

Fuel Cells: Compare Technologies, Fuel Supply and Useful Output

Compare fuel-cell applications using the complete system, fuel quality and supply, net electricity, useful heat, operating response and lifecycle emissions.

Electricity Demand: Read Load Curves and Evaluate Forecasts

Interpret electricity demand using energy, peak power, load shape, forecast assumptions and the resources available at the required time.

Transmission Grid: Understand Power Flow, Voltage and Constraints

Understand electricity delivery, real and reactive power, and the different constraints that a transmission upgrade must address.

Compressed-Air Energy Storage: Compare Designs and Performance

Compare compressed-air storage using heat management, net power, usable duration, complete energy inputs, site requirements and operating evidence.

Clean Energy Options: Compare Impacts and System Needs

Compare energy options using a defined service, lifecycle impacts, local constraints and the needs of the complete electricity system.

Organic Solar Cells: Evaluate Efficiency, Durability and Applications

Read organic photovoltaic results with their area, illumination and stability conditions, then assess evidence for a specific application.

Wind Turbine Blades: Understand Materials, Loads and Service Life

Understand blade structure, manufacturing evidence, fatigue and inspection, and evaluate realistic repair and end-of-service options.

Solar Energy in India: Choose a System for the Required Service

Separate rooftop electricity, essential-load backup and agricultural pumping, then prepare a site-specific solar brief and compare offers.

Distribution Voltage Regulation: Evaluate Voltage Quality and Energy Claims

Read distribution-voltage studies, distinguish voltage quality from energy savings, and evaluate a conservation voltage reduction comparison.

Generator Interconnection Relays: Understand Protection and Approval

Prepare an interconnection protection evidence package covering operating modes, relay functions, coordination, testing and utility approval.

Wind Farm Proposals: Evaluate Site Evidence and Community Impacts

Review a wind-farm proposal through its site studies, project stage, energy assumptions, community commitments and end-of-service responsibilities.

Industrial Biomass CHP: Evaluate Steam, Electricity and Fuel Supply

Assess an industrial biomass CHP proposal using process steam demand, net electricity, dependable fuel supply and a clear emissions boundary.

Hydrogen from Seawater and Sunlight: Evaluate the Research Claims

Interpret solar-hydrogen experiments using the complete energy and material inputs, gas measurements, durability and scale of the demonstrated system.

Assess waste, fuels and carbon management

Waste-to-Energy: Compare Recovery, Emissions and Disposal Tradeoffs

Assess municipal waste combustion using the waste hierarchy, net energy delivered, emissions records, ash handling and consistent comparison boundaries.

Biogas: Understand Feedstocks, Upgrading and Climate Claims

Trace a biogas project from feedstock to end use, then assess gas treatment, methane losses, energy use, digestate and the alternative waste pathway.

Carbon Capture and Storage: Evaluate the Whole Project

Evaluate carbon-capture claims across capture, transport and geological storage, distinguishing capture rate from net avoided emissions and project readiness.

Methane Gas Facts: Understand Sources, Energy and Climate Effects

Distinguish methane from fuel-gas mixtures and interpret emissions claims using mass, climate metrics, time horizons and system boundaries.

Hydrogen Power: Evaluate the Production-to-Electricity Chain

Trace hydrogen production, delivery, storage and power conversion to compare net electricity, total inputs, emissions and operating requirements.

Strategic Petroleum Reserve: Read Inventory and Release Data

Use official U.S. Strategic Petroleum Reserve data to distinguish oil inventory, storage capacity, release volumes, drawdown rates and delivery timing.

U.S. Oil Production: Read Trends, Revisions and Forecasts

Choose an EIA production series, keep units and periods consistent, and distinguish reported estimates, revisions, inventories and forecasts.

Gas Hydrates: Understand the Resource and Production Evidence

Distinguish gas-hydrate occurrence, resource estimates and field-test results from evidence of recoverable, commercially viable production.

Dissolved Oxygen at Hydropower Dams: Read Measurements and Aeration Claims

Interpret dissolved-oxygen concentration, saturation, sampling conditions and evidence for aeration at a hydropower dam.

Cellulosic Biofuel Costs: Evaluate Yield, Scale and Production Claims

Evaluate cellulosic ethanol cost claims by checking dry feedstock, conversion yield, plant utilization, system boundaries and evidence scale.

Offshore Oil Pipelines: Read Capacity, Throughput and Market Connections

Trace offshore crude from production to shore and distinguish pipeline capacity, measured throughput, ownership and refinery access.

Cellulose-to-Furan Fuels: Follow the Conversion and Yield Evidence

Trace cellulose through furan intermediates and distinguish reaction yield, process integration and finished-fuel performance.

Understand biofuel co-products

Camelina Meal as Animal Feed

Understand the oilseed meal’s potential nutritional role, processing constraints and species-specific feed requirements. Updated May 2026.

Background and historical reporting

These older articles cover research, product announcements, projects and policy developments in their period. Dates below are the original publication dates. Read equipment claims, prices and proposals in that historical context; use the practical guides above for current planning.

Generation and energy research

Fuels, resources and bioenergy

Transport, batteries and fuel cells

Electricity networks and markets

Equipment and building efficiency